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What does the simile in this text suggest? The president said that his belief in freedom of expression is as solid as the ground we stand on.
[ "The president's belief in freedom of expression is firm and unwavering.", "The president's belief in freedom of expression is recorded in a document." ]
0
closed choice
grade9
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. A simile uses like or as to compare two things that are not actually alike. The cat's fur was as dark as the night.
The text includes a simile, using like or as to compare two things that are not actually alike. The simile solid as the ground we stand on suggests that the president's belief in freedom of expression is firm and unwavering. The ground is solid and firm, which indicates that the president's belief is, too.
Would you find the word admire on a dictionary page with the following guide words? actually - afraid
[ "yes", "no" ]
0
yes or no
grade4
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since admire is between the guide words actually - afraid, it would be found on that page.
Based on this information, what is this plant's phenotype for the fruit texture trait?
[ "bumpy fruit", "smooth fruit" ]
1
In a group of cucumber plants, some individuals have bumpy fruit and others have smooth fruit. In this group, the gene for the fruit texture trait has two alleles. The allele for smooth fruit (f) is recessive to the allele for bumpy fruit (F). A certain cucumber plant from this group has the homozygous genotype ff for the fruit texture gene.
closed choice
grade7
natural science
biology
Genes to traits
Genetics vocabulary: dominant and recessive
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait. Some traits, like flower color in pea plants, are controlled by a single gene. Most plants and animals have a genotype made up of two alleles for these traits. These two alleles determine whether an organism is homozygous or heterozygous for the gene. An organism with two identical alleles for a gene is homozygous for that gene. A pea plant with the genotype FF or ff is homozygous for the flower color gene. An organism with two different alleles for a gene is heterozygous for that gene. A pea plant with the genotype Ff is heterozygous for the flower color gene. The types of alleles in an organism's genotype determine the organism's phenotype. Some alleles have types called dominant and recessive. These two types can cause different versions of a trait to appear as the organism's phenotype. A dominant allele causes its version of the trait to appear even when the organism also has a recessive allele for the gene. In pea plants, the F allele, which causes purple flowers, is dominant over the f allele. A pea plant with at least one F allele will have the F allele's version of the flower color trait. So, a plant with the genotype FF or Ff will have purple flowers. A recessive allele causes its version of the trait to appear only when the organism does not have any dominant alleles for the gene. In pea plants, the f allele, which causes white flowers, is recessive to the F allele. A pea plant with only f alleles will have the f allele's version of the flower color trait. So, a plant with the genotype ff will have white flowers.
The cucumber plant's genotype for the fruit texture gene is ff. The cucumber plant's genotype of ff has only f alleles. The f allele is for smooth fruit. So, the cucumber plant's phenotype for the fruit texture trait must be smooth fruit. To check this answer, consider whether the cucumber plant's alleles are dominant or recessive. The allele for smooth fruit (f) is recessive to the allele for bumpy fruit (F). This means F is a dominant allele, and f is a recessive allele. The cucumber plant's genotype of ff has only recessive alleles. An organism with only recessive alleles for a gene will have the recessive allele's version of the trait. So, the cucumber plant's phenotype for the fruit texture trait must be smooth fruit.
Which text uses the word factoid in its traditional sense?
[ "Oscar subscribed to an online newsletter about African wildlife; he enjoyed receiving daily factoids about the wild animals' natural habitats and behavior.", "Oscar seemed to know a lot about African wildlife, but it turned out that his knowledge was mostly based on factoids gleaned from unreliable websites." ]
1
closed choice
grade9
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be more commonly used, many people consider a word's traditional definition to be the correct usage. Being able to distinguish the different uses of a word can help you use it appropriately for different audiences. Britney perused her notes, carefully preparing for her exam. The traditional usage above is considered more standard. David perused the magazine, absentmindedly flipping through the pages. The nontraditional usage above is now commonly used, but traditional style guides generally advise against it.
The second text uses factoid in its traditional sense: something made up presented as a true fact. Oscar seemed to know a lot about African wildlife, but it turned out that his knowledge was mostly based on factoids gleaned from unreliable websites. The first text uses factoid in its nontraditional sense: a trivial but true fact. Oscar subscribed to an online newsletter about African wildlife; he enjoyed receiving daily factoids about the wild animals' natural habitats and behavior. Most style guides recommend to use the traditional sense of the word factoid because it is considered more standard.
What information supports the conclusion that Jennifer inherited this trait?
[ "Jennifer and her mother both wear their hair in braids.", "Jennifer's parents have red hair. They passed down this trait to Jennifer." ]
1
Read the description of a trait. Jennifer has red hair.
closed choice
grade3
natural science
biology
Heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
Which is scratchier?
[ "metal flute", "sandpaper" ]
1
closed choice
grade2
natural science
physics
Materials
Compare properties of materials
Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials. A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells.
Scratchy is a property. A scratchy material is rough and itchy against your skin. Look at each picture, one at a time. Imagine touching the material shown in each picture. Of the choices, the sandpaper is scratchier. If you touch a piece of sandpaper, it will feel rough and itchy.
Select the activity that doesn't belong.
[ "sweep", "scrub", "swing", "wipe" ]
2
closed choice
grade3
language science
vocabulary
Categories
Select the words that don't belong
Swing doesn't belong. Sweep, wipe, and scrub all name ways to clean.
Based on this information, what is Admiral's genotype for the body color gene?
[ "a gray body", "BB" ]
1
In a group of guppies, some individuals have a gray body and others have a golden body. In this group, the gene for the body color trait has two alleles. The allele B is for a gray body, and the allele b is for a golden body. Admiral, a guppy from this group, has a gray body. Admiral has two alleles for a gray body.
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's genotype for a gene is its combination of alleles for that gene. Admiral has two alleles for a gray body (B). So, Admiral's genotype for the body color gene is BB.
Compare the motion of three motorboats. Which motorboat was moving at the lowest speed?
[ "a motorboat that moved 140kilometers east in 5hours", "a motorboat that moved 235kilometers west in 5hours", "a motorboat that moved 205kilometers west in 5hours" ]
0
closed choice
grade3
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the kilometer. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about objects moving for the same amount of time. The object that is moving the slowest will go the shortest distance in that time. It is moving at the lowest speed.
Look at the distance each motorboat moved and the time it took to move that distance. The direction each motorboat moved does not affect its speed. Notice that each motorboat moved for 5 hours. The motorboat that moved 140 kilometers moved the shortest distance in that time. So, that motorboat must have moved at the lowest speed.
How long is a parking space?
[ "8 centimeters", "8 kilometers", "8 meters", "8 millimeters" ]
2
Select the best estimate.
closed choice
grade7
natural science
units-and-measurement
Units and measurement
Choose metric units of distance, mass, and volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. When you are using metric units, length can be written with units of millimeters, centimeters, meters, or kilometers. One meter contains 100 centimeters or 1,000 millimeters. So, 1 meter is larger than 1 centimeter, and 1 centimeter is larger than 1 millimeter. The tip of the pencil shown here is only 1 millimeter wide, but the pencil is about 16 centimeters long. A red fox is about 1 meter long. The Sydney Harbour Bridge in Australia is about 1,000 meters, or 1 kilometer, in length.
The best estimate for the length of a parking space is 8 meters. 8 millimeters and 8 centimeters are too short. 8 kilometers is too long.
Which word would you find on a dictionary page with the following guide words? member - musket
[ "mark", "mitt" ]
1
closed choice
grade4
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since mitt is between the guide words member - musket, it would be found on that page.
What does the allusion in this text suggest? When Diana claimed she had loaded the dishwasher before turning on Dancing with the Stars, her mother replied, "Your nose is growing!"
[ "Diana was trustworthy.", "Diana was lying." ]
1
closed choice
grade10
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. An allusion is a brief reference to something or someone well known, often from history or literature. "I'd better get home before I turn into a pumpkin!" Lila remarked.
The text uses an allusion, a brief reference to someone or something well known. The allusion nose is growing suggests that Diana was lying. In the story of Pinocchio, when Pinocchio lies, his nose grows longer.
Which logical fallacy is used in the text? In this election, we've seen the highest voter turnout ever recorded. If you have any doubts about Eric Hong's qualifications, just look at how many people have come out to vote for him.
[ "bandwagon fallacy: the assumption that the popular choice is automatically correct", "false causation: the assumption that because two things happened together, one caused the other" ]
0
closed choice
grade6
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | a personal attack meant to discredit one's opponent appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something red herring | the use of a completely unrelated topic in support of a claim A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a very broad claim based on very little evidence straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that Eric Hong is the most qualified candidate, because so many voters turned out to vote. However, even though many people voted for him, that doesn't necessarily mean that Eric Hong is the most qualified candidate. This illustrates a type of logical fallacy known as the bandwagon fallacy.
Select the mixture.
[ "sugar", "yogurt" ]
1
closed choice
grade2
natural science
physics
Mixtures
Identify mixtures
A pure substance is made of only one type of matter. A mixture is made of two or more types of matter mixed together.
Select the one animal that has all of the amphibian traits listed above.
[ "Green frogs have moist skin. Green frog tadpoles hatch from eggs without shells and live underwater. The adult frogs live on land near ponds and rivers. They may jump into the water to hide from predators.", "Western gorillas have black, gray, or brown fur. Adult males are sometimes called silverbacks because they have often have gray fur on their backs. Female western gorillas feed their offspring milk." ]
0
Amphibians are a group of animals with similar traits. The following traits can be used to identify amphibians: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Amphibians have the following traits: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A green frog has the following traits: It spends part of its life in water and part on land. It has moist skin. It makes eggs with no shells. A green frog has the traits of an amphibian. A green frog is an amphibian. A western gorilla has the following traits: It feeds its offspring milk. It has fur. A western gorilla does not have all of the traits of an amphibian. A western gorilla is a mammal.
Is the following trait inherited or acquired? Dale has a scar on his right knee.
[ "inherited", "acquired" ]
1
closed choice
grade5
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
Children do not inherit their parent's scars. Instead, scars are caused by the environment. People can get scars after they get hurt. So, having a scar is an acquired trait.
Would you find the word shave on a dictionary page with the following guide words? scissors - site
[ "no", "yes" ]
1
yes or no
grade5
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since shave is between the guide words scissors - site, it would be found on that page.
According to the passage, which statement is true?
[ "The House of Representatives is a part of Congress.", "Congress does not have legislative power." ]
0
The Legislative Branch is described in Article I of the United States Constitution. Read Section 1 of Article I. Then answer the question. All legislative powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives. legislative: law-making vested in: given to consist: be made up of
closed choice
grade8
social science
civics
Government
The Legislative Branch
In the 1970s, very few companies made and sold personal computers. Nobody knew if consumers would want to buy them. But when computers turned out to be popular with consumers, more companies started making and selling them. What happened to the overall supply of personal computers?
[ "The supply went down.", "The supply went up." ]
1
closed choice
grade7
social science
economics
Supply and demand
Understand overall supply and demand
Overall supply is the total amount of a good or service that producers make and sell. There are several things that can make overall supply go up or down. The table below shows how changes to these things might affect overall supply. | Resources | Number of producers or suppliers | Expected change in demand Supply goes up | when resources cost less or are easier to get | when there are more producers or suppliers | when demand is expected to go up Supply goes down | when resources cost more or are harder to get | when there are fewer producers or suppliers | when demand is expected to go down Producers are people or companies that make goods or provide services. Suppliers are people or companies that sell goods or services. New inventions or technologies can also help workers produce goods and services more quickly. As a result of these changes, the supply of a good or service will often go up.
Some of the first computer companies became successful quickly. Other companies saw that a lot of people wanted to buy personal computers. So more companies started selling them. The number of producers went up. So, the supply of personal computers went up.
Which sentence is more formal?
[ "Rice is super important for billions of people around the world.", "Rice is the staple food for billions of people around the world." ]
1
closed choice
grade5
language science
writing-strategies
Author's purpose and tone
Which sentence is more formal?
Formal writing is used for essays, business letters, and reports. The following types of informal language should be avoided in formal writing: Type | Examples slang | cool, awesome idioms | knock your socks off conversational language | gonna, kinda, yeah abbreviated language | ASAP, FYI overly simple or imprecise language | he got some stuff at the store contractions | can't, won't Contractions are not as informal as the other types, but they should be used sparingly in formal writing. Compare the following sentences. The first is informal. The second is formal. Informal: Yeah, ostriches can't fly, but they're awesome runners. Formal: Though ostriches are flightless, they are remarkably adept runners.
The second sentence is less formal. You can tell because it uses conversational language (super). The first sentence uses formal language in place of the conversational language, so it is more formal overall.
Last year, there were seven men's clothing stores on Main Street in Hampton. This year, there are only three. What probably happened to the overall supply of men's shirts in Hampton?
[ "The supply probably went down.", "The supply probably went up." ]
0
closed choice
grade8
social science
economics
Supply and demand
Understand overall supply and demand
Overall supply is the total amount of a good or service that producers make and sell. There are several things that can make overall supply go up or down. The table below shows how changes to these things might affect overall supply. | Resources | Number of producers or suppliers | Expected change in demand Supply goes up | when resources cost less or are easier to get | when there are more producers or suppliers | when demand is expected to go up Supply goes down | when resources cost more or are harder to get | when there are fewer producers or suppliers | when demand is expected to go down Producers are people or companies that make goods or provide services. Suppliers are people or companies that sell goods or services. New inventions or technologies can also help workers produce goods and services more quickly. As a result of these changes, the supply of a good or service will often go up.
When four men's clothing stores closed on Main Street, the number of suppliers went down. There were fewer stores selling men's shirts. So, the supply of men's shirts probably went down.
Which figure of speech is used in this text? Jaden's leaving his job? That's old news. He's been planning that for months.
[ "oxymoron", "euphemism" ]
0
closed choice
grade12
language science
figurative-language
Literary devices
Classify the figure of speech: euphemism, hyperbole, oxymoron, paradox
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic. The head of Human Resources would never refer to firing people, only to laying them off. Hyperbole is an obvious exaggeration that is not meant to be taken literally. I ate so much that I think I might explode! An oxymoron is a joining of two seemingly contradictory terms. Some reviewers are calling this book a new classic. A paradox is a statement that might at first appear to be contradictory, but that may in fact contain some truth. Always expect the unexpected.
The text uses an oxymoron, a joining of two seemingly contradictory terms. Old news is a contradiction, because news is recent information.
Which is a simple sentence?
[ "First, Leo planted the geraniums in a clay pot, and then he placed the pot on a sunny windowsill in his kitchen.", "Babe Ruth hit 714 home runs during his baseball career but struck out 1,330 times." ]
1
closed choice
grade6
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple, compound, or complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought. It can stand alone as a sentence. A dependent clause is not a complete thought. It cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alone. It is independent. after we pick up Kevin from work The clause cannot stand alone. It is dependent. A simple sentence is made up of a single independent clause. Ben and I spent all day relaxing by the pool. Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate. In the winter, Ben usually wears his heavy coat. Ben usually wears his heavy coat in the winter. A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so. We saw a flash of lightning, and seconds later we heard the rumble of thunder. A complex sentence is made up of an independent clause and a dependent clause. The dependent clause usually begins with a subordinating conjunction such as after, although, as, because, before, if, since, unless, until, when, or while. If she ever gets the chance, Terri would love to visit the Egyptian pyramids.
The second sentence is the simple sentence. It is a single independent clause. Babe Ruth hit 714 home runs during his baseball career but struck out 1,330 times.
Select the plant.
[ "Barrel cactuses grow in the ground.", "Gorillas eat leaves, fruits, and insects.", "Honey bees walk and fly.", "Kangaroos hop and swim." ]
0
closed choice
grade3
natural science
biology
Classification
Identify plants and animals
Plants and animals are living things. Living things are called organisms. Plants come in many shapes and sizes. Most plants grow in the ground. They might grow leaves, flowers, and fruit. Plants cannot move around on their own like animals can. Animals also come in many shapes and sizes. Most animals can move around. Animals might run, swim, jump, or fly. Animals eat plants or other organisms for food.
A kangaroo is an animal. It hops and swims. Kangaroos hop to move around. They use their large tails for balance while hopping. A gorilla is an animal. It eats leaves, fruits, and insects. Gorillas live in groups called troops. A honey bee is an animal. It walks and flies. A honey bee is an insect. Honey bees live in large groups called colonies. A barrel cactus is a plant. It grows in the ground. A barrel cactus is covered in spines. The spines protect the barrel cactus from being eaten by animals.
Which tense does the sentence use? Mr. Meyer buys a new coat.
[ "future tense", "past tense", "present tense" ]
2
closed choice
grade2
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in present tense. You can tell because it uses a present-tense verb, buys. The verb ends in -s and tells you about something that is true or happening now.
What is the mass of an elephant?
[ "6,165 kilograms", "6,165 grams" ]
0
Select the better estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose metric units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using metric units, mass may be written with units of grams or kilograms. There are 1,000 grams in 1 kilogram. So, 1 gram is much less than 1 kilogram. A paper clip has a mass of about 1 gram, while a textbook has a mass of about 1 kilogram.
The better estimate for the mass of an elephant is 6,165 kilograms. 6,165 grams is too light.
Select the invertebrate.
[ "castor bean tick", "zebra dove", "Solomon leaf frog", "harvest mouse" ]
0
Hint: Insects, spiders, and worms are invertebrates.
closed choice
grade5
natural science
biology
Classification
Identify vertebrates and invertebrates
Vertebrates and invertebrates are both groups of animals. A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange. An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body.
A zebra dove is a bird. Like other birds, a zebra dove is a vertebrate. It has a backbone. A harvest mouse is a mammal. Like other mammals, a harvest mouse is a vertebrate. It has a backbone. A Solomon leaf frog is an amphibian. Like other amphibians, a Solomon leaf frog is a vertebrate. It has a backbone. A castor bean tick is an insect. Like other insects, a castor bean tick is an invertebrate. It does not have a backbone. It has an exoskeleton.
Using only these supplies, which question can Lorenzo investigate with an experiment?
[ "Does vinegar separate faster when stirred together with olive oil or with coconut oil?", "Does vegetable oil separate faster when stirred together with vinegar or with water?", "Does vegetable oil separate faster when stirred together with cold water or with hot water?" ]
1
Lorenzo mixes oil and vinegar to make salad dressing. He notices that after a few minutes, the oil and vinegar separate. He wonders what factors affect how quickly liquids separate. So, he decides to design an experiment. He has the following supplies available: three glass bottles olive oil vegetable oil vinegar cold water
closed choice
grade8
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Based on this information, what is Muffin's genotype for the fur color gene?
[ "brown fur", "ff" ]
1
In a group of rabbits, some individuals have black fur and others have brown fur. In this group, the gene for the fur color trait has two alleles. The allele F is for black fur, and the allele f is for brown fur. Muffin, a rabbit from this group, has brown fur. Muffin has two alleles for brown fur.
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's genotype for a gene is its combination of alleles for that gene. Muffin has two alleles for brown fur (f). So, Muffin's genotype for the fur color gene is ff.
What kind of sentence is this? Which of these professions do you think requires more formal education—being a lawyer or being a college professor?
[ "exclamatory", "interrogative", "imperative" ]
1
closed choice
grade7
language science
punctuation
Sentences, fragments, and run-ons
Is the sentence declarative, interrogative, imperative, or exclamatory?
There are four kinds of sentences. A declarative sentence is a statement, and it always ends with a period. The nurse told Mr. Abrams to roll up his sleeve so that she could check his blood pressure. An interrogative sentence is a question, and it always ends with a question mark. Do you have any plans for the upcoming weekend? An imperative sentence is a command. It makes a request or tells someone to do something, and it usually ends with a period. If the command shows strong feeling, it ends with an exclamation point. For this assignment, use references to support your claims. Don't drive so quickly in the construction zone! An exclamatory sentence is like a statement, but it shows surprise or strong feeling. An exclamatory sentence always ends with an exclamation point. I can't wait to travel through Europe this summer!
The sentence asks something, and it ends with a question mark. It is an interrogative sentence.
Based on this information, what is Amigo's phenotype for the coat pattern trait?
[ "white spots", "solid coloring" ]
1
In a group of cows, some individuals have solid coloring and others have white spots. In this group, the gene for the coat pattern trait has two alleles. The allele for solid coloring (A) is dominant over the allele for white spots (a). Amigo is a cow from this group. Amigo has the heterozygous genotype Aa for the coat pattern gene.
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: dominant and recessive
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait. Some traits, like flower color in pea plants, are controlled by a single gene. Most plants and animals have a genotype made up of two alleles for these traits. These two alleles determine whether an organism is homozygous or heterozygous for the gene. An organism with two identical alleles for a gene is homozygous for that gene. A pea plant with the genotype FF or ff is homozygous for the flower color gene. An organism with two different alleles for a gene is heterozygous for that gene. A pea plant with the genotype Ff is heterozygous for the flower color gene. The types of alleles in an organism's genotype determine the organism's phenotype. Some alleles have types called dominant and recessive. These two types can cause different versions of a trait to appear as the organism's phenotype. A dominant allele causes its version of the trait to appear even when the organism also has a recessive allele for the gene. In pea plants, the F allele, which causes purple flowers, is dominant over the f allele. A pea plant with at least one F allele will have the F allele's version of the flower color trait. So, a plant with the genotype FF or Ff will have purple flowers. A recessive allele causes its version of the trait to appear only when the organism does not have any dominant alleles for the gene. In pea plants, the f allele, which causes white flowers, is recessive to the F allele. A pea plant with only f alleles will have the f allele's version of the flower color trait. So, a plant with the genotype ff will have white flowers.
You need to determine Amigo's phenotype for the coat pattern trait. First, consider the alleles in Amigo's genotype for the coat pattern gene. Then, decide whether these alleles are dominant or recessive. The allele for solid coloring (A) is dominant over the allele for white spots (a). This means A is a dominant allele, and a is a recessive allele. Amigo's genotype of Aa has one dominant allele and one recessive allele. An organism with at least one dominant allele for a gene will have the dominant allele's version of the trait. So, Amigo's phenotype for the coat pattern trait must be solid coloring.
What is the volume of a can of soda pop?
[ "330 liters", "330 milliliters" ]
1
Select the better estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters. There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter. A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters.
The better estimate for the volume of a can of soda pop is 330 milliliters. 330 liters is too much.
Complete the text. After losing the Battles of Saratoga, British leaders changed their plans for the war. In 1778, they decided their main goal should be to control ().
[ "the Southern Colonies", "the Middle Colonies", "New England", "the port of New Orleans" ]
0
closed choice
grade4
social science
us-history
The American Revolution
The American Revolution: conclusion and aftermath
In 1778, the British leaders decided their main goal should be to control the Southern Colonies. After the Battles of Saratoga, the British gave up hope of controlling New England or the Middle Colonies. The port of New Orleans was under Spanish control.
What do these two changes have in common? tearing a piece of paper pouring milk on oatmeal
[ "Both are caused by heating.", "Both are only physical changes.", "Both are chemical changes.", "Both are caused by cooling." ]
1
closed choice
grade3
natural science
chemistry
Physical and chemical change
Compare physical and chemical changes
Chemical changes and physical changes are two common ways matter can change. In a chemical change, the type of matter changes. The types of matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. When paper gets hot enough, it re­acts with oxygen in the air and burns. The paper and oxygen change into ash and smoke. In a physical change, the type of matter stays the same. The types of matter before and after a physical change are always the same. A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, ice melting is a physical change that can be caused by heating. Ice and liquid water are made of the same type of matter: water. The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change.
Step 1: Think about each change. Tearing a piece of paper is a physical change. The paper tears into pieces. But each piece is still made of paper. Pouring milk on oatmeal is a physical change. The oatmeal and milk form a creamy mixture. But making this mixture does not form a different type of matter. Step 2: Look at each answer choice. Both are only physical changes. Both changes are physical changes. No new matter is created. Both are chemical changes. Both changes are physical changes. They are not chemical changes. Both are caused by heating. Neither change is caused by heating. Both are caused by cooling. Neither change is caused by cooling.
Which figure of speech is used in this text? Tony's leaving his job? That's old news. He's been planning that for months.
[ "chiasmus", "oxymoron" ]
1
closed choice
grade11
language science
figurative-language
Literary devices
Classify the figure of speech: review
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Anaphora is the repetition of the same word or words at the beginning of several phrases or clauses. We are united. We are powerful. We are winners. Antithesis involves contrasting opposing ideas within a parallel grammatical structure. I want to help, not to hurt. Apostrophe is a direct address to an absent person or a nonhuman entity. Oh, little bird, what makes you sing so beautifully? Assonance is the repetition of a vowel sound in a series of nearby words. Try to light the fire. Chiasmus is an expression in which the second half parallels the first but reverses the order of words. Never let a fool kiss you or a kiss fool you. A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic. The head of Human Resources would never refer to firing people, only to laying them off. Hyperbole is an obvious exaggeration that is not meant to be taken literally. I ate so much that I think I might explode! An oxymoron is a joining of two seemingly contradictory terms. Some reviewers are calling this book a new classic. A paradox is a statement that might at first appear to be contradictory, but that may in fact contain some truth. Always expect the unexpected. Understatement involves deliberately representing something as less serious or important than it really is. As you know, it can get a little cold in the Antarctic.
The text uses an oxymoron, a joining of two seemingly contradictory terms. Old news is a contradiction, because news is recent information.
Which text uses the word travesty in its traditional sense?
[ "Devin realized that his essay about the Space Race was a bit inaccurate, but he still thought it a travesty that such an entertaining essay should receive a poor grade.", "Devin's ill-researched essay about the Space Race received a poor grade because it presented such a travesty of the actual historical events." ]
1
closed choice
grade9
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be more commonly used, many people consider a word's traditional definition to be the correct usage. Being able to distinguish the different uses of a word can help you use it appropriately for different audiences. Britney perused her notes, carefully preparing for her exam. The traditional usage above is considered more standard. David perused the magazine, absentmindedly flipping through the pages. The nontraditional usage above is now commonly used, but traditional style guides generally advise against it.
The first text uses travesty in its traditional sense: a ridiculous imitation; a parody. Devin's ill-researched essay about the Space Race received a poor grade because it presented such a travesty of the actual historical events. The second text uses travesty in its nontraditional sense: a disappointment or a tragedy. Devin realized that his essay about the Space Race was a bit inaccurate, but he still thought it a travesty that such an entertaining essay should receive a poor grade. Most style guides recommend to use the traditional sense of the word travesty because it is considered more standard.
Would you find the word musket on a dictionary page with the following guide words? maid - mist
[ "yes", "no" ]
1
yes or no
grade2
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on.
Put the words in alphabetical order. Since musket is not between the guide words maid - mist, it would not be found on that page.
Select the living thing.
[ "swing set", "koala", "brick wall", "bathtub" ]
1
closed choice
grade4
natural science
biology
Classification
Identify living and nonliving things
All living things are made up of cells. Plants, animals, and some fungi have many cells. Other living things are made up of just one cell. All living things need food and water. Water helps living things break down food and remove waste. Food gives living things energy. They use energy from food to grow and change. All living things sense changes in their environment. Living things might sense changes by seeing, smelling, hearing, or feeling. Living things can respond to the changes they sense.
A brick wall is not a living thing. Brick walls do not have all of the traits of living things. They do not grow or respond to their environment. They do not need food or water. A swing set is not a living thing. Swing sets do not have all of the traits of living things. They do not grow or respond to their environment. They do not need food or water. A bathtub is not a living thing. Bathtubs do not have all of the traits of living things. They do not grow or respond to their environment. They do not need food or water. A koala is a living thing. Koalas grow and respond to their environment. They need food and water. Koalas are made up of many cells.
Which is harder?
[ "toothpaste", "wood chair" ]
1
closed choice
grade2
natural science
physics
Materials
Compare properties of materials
Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials. A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells.
Hard is a property. A hard material keeps its shape when you press on it with your finger. Look at each picture, one at a time. Imagine pushing on the material shown in each picture. Of the choices, the wood chair is harder. If you squeeze a piece of wood, it will not change shape.
Is this a run-on sentence? In 2014, researchers discovered forgotten satellite images of Earth from the early 1960s that, when compared with recent satellite photographs, reveal how humans have altered the face of the planet.
[ "no", "yes" ]
0
yes or no
grade12
language science
writing-strategies
Sentences, fragments, and run-ons
Identify run-on sentences
A sentence is a group of words that expresses a complete thought. The band I'm in has been rehearsing daily because we have a concert in two weeks. A run-on sentence is formed when two sentences are run together, joined by just a comma or by no punctuation at all. If only a comma is used, the run-on is called a comma splice. The band I'm in has been rehearsing daily, we have a concert in two weeks. The band I'm in has been rehearsing daily we have a concert in two weeks. There are several ways to fix a run-on sentence: Use stronger punctuation, such as a period or a semicolon. The band I'm in has been rehearsing daily. We have a concert in two weeks. The band I'm in has been rehearsing daily; we have a concert in two weeks. Use a comma and a coordinating conjunction to create a compound sentence. Coordinating conjunctions include and, but, or, and so. The band I'm in has been rehearsing daily, and we have a concert in two weeks. Use a subordinating conjunction or a relative pronoun to create a complex sentence. Subordinating conjunctions include after, although, as, because, before, if, since, unless, until, when, and while. Relative pronouns include that, which, who, whom, and whose. The band I'm in has been rehearsing daily since we have a concert in two weeks.
This is not a run-on sentence. It is not formed from two sentences that have been run together without appropriate punctuation. In 2014, researchers discovered forgotten satellite images of Earth from the early 1960 s that, when compared with recent satellite photographs, reveal how humans have altered the face of the planet.
What is the mass of an eraser?
[ "38 kilograms", "38 grams" ]
1
Select the better estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose metric units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using metric units, mass may be written with units of grams or kilograms. There are 1,000 grams in 1 kilogram. So, 1 gram is much less than 1 kilogram. A paper clip has a mass of about 1 gram, while a textbook has a mass of about 1 kilogram.
The better estimate for the mass of an eraser is 38 grams. 38 kilograms is too heavy.
Which word would you find on a dictionary page with the following guide words? these - tomato
[ "tint", "tender" ]
0
closed choice
grade4
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since tint is between the guide words these - tomato, it would be found on that page.
Which tense does the sentence use? The voyage lasted for several months.
[ "future tense", "present tense", "past tense" ]
2
closed choice
grade5
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in past tense. You can tell because it uses a past-tense verb, lasted. The verb ends in -ed and tells you about something that has already happened.
Which is a compound sentence?
[ "The tailor measures the length of the pant leg.", "The captain saw storm clouds, so he steered the ship back to shore." ]
1
closed choice
grade5
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or a compound predicate, but they are not compound sentences. Anna and James will watch the fireworks tonight. This simple sentence has a compound subject, Anna and James. The singers bowed and walked off the stage. This simple sentence has a compound predicate, bowed and walked off the stage. Some simple sentences have introductory phrases, but they are not compound sentences. The introductory phrase is part of the predicate. In the winter, Farmer Ben wears his heavy coat. This is a simple sentence. There is one subject, Farmer Ben, and one predicate, wears his heavy coat in the winter.
The second sentence is the compound sentence. It is made up of two simple sentences joined by a comma and the conjunction so. The captain saw storm clouds, so he steered the ship back to shore.
How long does it take to sing the ABC song?
[ "22 seconds", "22 minutes" ]
0
Select the better estimate.
closed choice
grade2
natural science
units-and-measurement
Units and measurement
Choose units of time
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Imagine being told that the bus leaves in 7. You might be thinking, 7 what? Does the bus leave in 7 minutes? 7 seconds? The number 7 on its own does not give you much information about when the bus is leaving. That is because the units are missing. Time is usually measured in units of seconds, minutes, or hours. It takes about 1 second to sneeze and 1 minute to get dressed in the morning. It takes about 1 hour to bake a pie in the oven. There are 60 seconds in 1 minute. So, 1 second is much less than 1 minute. There are 60 minutes in 1 hour. So, 1 minute is much less than 1 hour.
The better estimate for how long it takes to sing the ABC song is 22 seconds. 22 minutes is too slow.
What is the source of the allusion in the sentence below? The headline read: "Smart Phones Becoming Big Brother."
[ "literature", "a song" ]
0
closed choice
grade9
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately.
The source of the allusion Big Brother is literature. George Orwell's novel 1984 focuses on a totalitarian society in which the citizens are frequently reminded that their leader, Big Brother, is always watching. The allusion Big Brother means a threatening power that monitors all aspects of people's lives.
What information supports the conclusion that Jared acquired this trait?
[ "Jared likes to look at butterflies and beetles.", "Jared learned to identify insects by reading many books about insects." ]
1
Read the description of a trait. Jared is good at identifying insects.
closed choice
grade6
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring.
What information supports the conclusion that Betty acquired this trait?
[ "Betty is most interested in plant biology.", "Betty learned biology by doing experiments." ]
1
Read the description of a trait. Betty knows a lot about biology.
closed choice
grade3
natural science
biology
Heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
Using only these supplies, which question can Becky investigate with an experiment?
[ "Do small rocks or large rocks skip more times when thrown across the river?", "Do round rocks or flat rocks skip more times when thrown across the river?", "Do rocks skip more times when thrown across a river or across a pond?" ]
0
Becky likes to skip rocks at the river. She notices that some of the rocks she throws skip off the surface of the water many times, while others skip once and then sink. She wonders what factors affect how well rocks skip on the water. So, she decides to design an experiment. She has the following supplies available: 10 small flat rocks 10 large flat rocks access to the river by her school
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Based on this information, what is Bolt's phenotype for the coat pattern trait?
[ "solid coloring", "AA" ]
0
In a group of cows, some individuals have solid coloring and others have white spots. In this group, the gene for the coat pattern trait has two alleles. The allele A is for solid coloring, and the allele a is for white spots. Bolt, a cow from this group, has solid coloring. Bolt has two alleles for solid coloring.
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's phenotype for a trait is its observable version of that trait. Bolt's observable version of the coat pattern trait is solid coloring. So, Bolt's phenotype for the coat pattern trait is solid coloring.
Which tense does the sentence use? At the party, the sisters danced together.
[ "past tense", "present tense", "future tense" ]
0
closed choice
grade2
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in past tense. You can tell because it uses a past-tense verb, danced. The verb ends in -ed and tells you about something that has already happened.
Which sentence states a fact?
[ "Spinach tastes worse than any other vegetable.", "The spinach plant is native to Asia." ]
1
closed choice
grade5
language science
writing-strategies
Developing and supporting arguments
Distinguish facts from opinions
A fact is something that can be proved to be true. The month of July has more days than the month of June. This is a fact. It can be proved by looking at a calendar and counting the number of days in each month. An opinion is something that a person believes, thinks, or feels. An opinion cannot be proved true. July is a better month than June for camping. This is an opinion. People may have different opinions about which month is "better" for camping.
The first sentence states a fact. The spinach plant is native to Asia. It can be proved by looking up information about spinach. The second sentence states an opinion. Spinach tastes worse than any other vegetable. Worse shows what a person believes, thinks, or feels. Another person might have a different opinion about what makes one vegetable taste worse than another.
Which sentence states a fact?
[ "During the Civil War, Frederick Douglass spoke to President Abraham Lincoln about the treatment of African American soldiers.", "Of all those who fought to put an end to slavery in America, the writer and abolitionist Frederick Douglass had the greatest influence." ]
0
closed choice
grade6
language science
writing-strategies
Developing and supporting arguments
Distinguish facts from opinions
A fact is something that can be proved by research or observation. Napoleon Bonaparte was shorter than King Louis XVI. The statement above is a fact. The statement can be proved by researching the height of each man and comparing them. An opinion is something that a person believes, thinks, or feels. An opinion cannot be proved. Napoleon Bonaparte was a better leader than King Louis XVI. The statement above is an opinion. People can have different ideas about what makes someone a "better" leader, so the statement cannot be proved.
The second sentence states a fact. During the Civil War, Frederick Douglass spoke to President Abraham Lincoln about the treatment of African American soldiers. It can be proved by reading Frederick Douglass's autobiography. The first sentence states an opinion. Of all those who fought to put an end to slavery in America, the writer and abolitionist Frederick Douglass had the greatest influence. Most influential shows what a person believes, thinks, or feels. Another person might have a different opinion about which abolitionist had the greatest influence.
Which logical fallacy is used in the text? How do I know that Polly is the most intelligent person in our geometry class? I know because she's so smart.
[ "guilt by association: a negative association intended to discredit someone or something", "circular reasoning: an argument that supports a claim with the claim itself" ]
1
closed choice
grade8
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | a personal attack meant to discredit one's opponent appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something red herring | the use of a completely unrelated topic in support of a claim A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a very broad claim based on very little evidence straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that Polly is intelligent because she's smart. However, the "evidence" is just a restatement of the claim itself. This illustrates a type of logical fallacy known as circular reasoning.
What is the mass of a full bag of groceries?
[ "9 tons", "9 ounces", "9 pounds" ]
2
Select the best estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose customary units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using customary units, mass may be written with units of ounces, pounds, or tons. There are 16 ounces in 1 pound and 2,000 pounds in 1 ton. So, 1 ounce is less than 1 pound and much less than 1 ton. A slice of bread has a mass of about 1 ounce, while a can of beans has a mass of about 1 pound. A small car has a mass of about 1 ton.
The best estimate for the mass of a full bag of groceries is 9 pounds. 9 ounces is too light and 9 tons is too heavy.
Complete the sentence so that it uses personification. Molly finally found her phone () under the bed.
[ "hiding", "missing" ]
0
closed choice
grade9
language science
writing-strategies
Creative techniques
Use personification
Personification is giving human characteristics to nonhuman things. It is a figure of speech that can be used to make writing more interesting or to emphasize a point. The trees danced in the wind. The word danced describes the trees as if they were people. Unlike people, however, trees can't actually dance. Instead, the personification suggests that the trees are moving.
Complete the sentence with the word hiding. It describes the phone as if it were a person who is hiding.
Select the elementary substance.
[ "fluoromethane (CH3F)", "copper (Cu)", "hydrogen sulfide (H2S)" ]
1
closed choice
grade5
natural science
chemistry
Atoms and molecules
Identify elementary substances and compounds using chemical formulas
Every substance around you is made of one or more chemical elements, or types of atoms. Substances that are made of only one chemical element are elementary substances. Substances that are made of two or more chemical elements bonded together are compounds. Every chemical element is represented by its own symbol. For some elements, the symbol is one capital letter. For other elements, the symbol is one capital letter and one lowercase letter. For example, the symbol for the element fluorine is F, and the symbol for the element beryllium is Be. The symbol for each element in a substance is shown in the substance's chemical formula. An elementary substance is represented by a chemical formula that contains only one symbol. The symbol may be followed by a subscript. A subscript is text that is smaller and placed lower than the normal line of text. A subscript is included when the atoms in the elementary substance are bonded to form molecules. The subscript tells you the number of atoms in each molecule. For example, the chemical formula for the elementary substance oxygen is O2. The formula has a subscript of 2. This subscript tells you that there are two atoms in the molecule represented by this chemical formula. The chemical element represented by the symbol O is also called oxygen. So, the formula O2 tells you that each molecule of O2 contains two oxygen atoms. A compound is represented by a chemical formula that contains multiple symbols. For example, in the compound beryllium fluoride, there is one beryllium atom for every two fluorine atoms. This combination is shown in the compound's chemical formula, BeF2. In the formula, the symbol Be represents one beryllium atom. The symbol F followed by the subscript 2 represents two fluorine atoms.
Look at the chemical formula for each substance, and count the number of symbols in the formula. Then, decide if the substance is an elementary substance. The chemical formula for fluoromethane contains three symbols: C for carbon, H for hydrogen, and F for fluorine. So, fluoromethane is made of three chemical elements bonded together. Substances that are made of two or more chemical elements bonded together are compounds. So, fluoromethane is a compound, not an elementary substance. The chemical formula for hydrogen sulfide contains two symbols: H for hydrogen and S for sulfur. So, hydrogen sulfide is made of two chemical elements bonded together. Substances that are made of two or more chemical elements bonded together are compounds. So, hydrogen sulfide is a compound, not an elementary substance. The chemical formula for copper contains one symbol: Cu. So, copper is made of one chemical element. Substances that are made of one chemical element are elementary substances. So, copper is an elementary substance.
Which change best matches the sentence? A rock from outer space hits Earth's surface.
[ "landslide", "erosion", "meteorite crash" ]
2
closed choice
grade3
natural science
earth-science
Earth events
Classify changes to Earth's surface II
Complete the statement. Assume that the book's mass did not change. The gravitational potential energy stored between the book and Earth () as the book fell toward the ground.
[ "decreased", "stayed the same", "increased" ]
0
Read the text about an object in motion. Harold knocked a book off a bookshelf. The book fell to the ground.
closed choice
grade7
natural science
physics
Kinetic and potential energy
Identify changes in gravitational potential energy
Gravitational potential energy is stored between any two objects. So, for every object on or near Earth, there is gravitational potential energy stored between the object and Earth. The amount of gravitational potential energy stored between an object and Earth depends on the mass of the object. The amount of gravitational potential energy also depends on the distance between the object and the center of Earth. This distance increases when the object moves higher and decreases when the object moves lower. If the distance between an object and the center of Earth changes, the gravitational potential energy stored between the object and Earth will change. The table below shows how this change can happen. When an object's mass stays the same and its distance from the center of Earth... | Gravitational potential energy stored between the object and Earth... increases | increases decreases | decreases stays the same | stays the same
Think about how the distance between the book and the center of Earth changed. The ground is lower than the bookshelf. As the book fell toward the ground, the distance between the book and the center of Earth decreased. So, the gravitational potential energy stored between the book and Earth decreased as the book fell toward the ground.
What does this Works Cited entry indicate about the cited work? Poniewozik, James. "TV Makes a Too-Close Call." Time 20 Nov. 2000: 70–71. Print.
[ "It is a book.", "It appears on pages 70–71.", "Time is the publisher." ]
1
closed choice
grade11
language science
reference-skills
Research skills
Understand a Works Cited entry (MLA 7th edition)
When writing research papers, you will often be asked to follow a particular style guide for your citations. One popular style guide is the Modern Language Association (MLA) Handbook. Below are the basic formats for some common types of Works Cited entries. Consult the MLA Handbook for a complete list. Books: Format | Author(s). Book Title. City of Publication: Publisher, Year of Publication. Medium of Publication. Example | Austen, Jane. Pride and Prejudice. New York: Dover Publications, 1995. Print. Essays, short stories, or poems in an anthology or book: Format | Author(s). "Essay, Poem, or Short Story Title." Anthology or Book Title. Ed. Editor Name. City of Publication: Publisher, Year of Publication. Page Number(s). Medium of Publication. Example | James, Henry. "The Middle Years." The Oxford Book of American Short Stories. Ed. Joyce Carol Oates. Oxford: Oxford UP, 2013. 116-135. Print. Magazine and newspaper articles: Format | Author(s). "Article Title." Title of Magazine or Newspaper Date of Publication: Page(s). Medium of Publication. Example | Hayes, David J., and James H. Stock. "The Real Cost of Coal." New York Times 24 Mar. 2015: n. pag. Web. 25 Mar. 2015. Journal articles: Format | Author(s). "Article Title." Title of Journal Volume.Issue (Year): Page(s). Medium of Publication. Example | Gillette, Jane, et al. "Human Simulations of Vocabulary Learning." Cognition 73.2 (1999): 135-176. Print. Web pages: Format | Author(s). "Page Title." Name of Website. Publisher, Date of Publication. Medium of Publication. Date of Access. Example | Gunn, Janelle P., and Lauren E. Owens. "How to Slash Sodium from Your Diet." Livestrong.com. Demand Media, 30 Mar. 2015. Web. 31 Mar. 2015. Additional guidelines: Author Names. The first author's name is written in last name, first name format (Smith, Jane). Additional author names are written in first name last name format (Smith, Jane, and John Doe). If there are more than three authors, the first author's name is followed by "et al.," which stands for and others (e.g., Smith, Jane, et al.). Medium of Publication. Each entry must include information about what form the content was communicated in. The most common mediums are "Print" and "Web," but other possibilities include "Film," "E-mail," and "Lecture." Whenever the Medium of Publication is "Web," the date of access (the day, month, and year the webpage was viewed) must be listed directly after the Medium of Publication. Editors and Translators. If a work has an editor or a translator, this information must be added to the Works Cited entry using the appropriate abbreviation. "Ed." stands for edited by. "Trans." stands for translated by. Missing Information. If a work has no known author, the author section of the citation is simply left out. If a work has no available page numbers, the abbreviation "n. pag." is used instead. If a work has no available publication date, the abbreviation "n.d." is used instead. If a work has no available publisher or no available city of publication, the abbreviation "n.p." is used instead.
Look closely at the Works Cited entry: Poniewozik, James. "TV Makes a Too-Close Call." Time 20 Nov. 2000: 70–71. Print. You can tell that the cited work appears on pages 70–71 by looking at the page numbers, which appear after the date of publication.
Which text uses the word factoid in its traditional sense?
[ "As a geneticist, Camille enjoys watching science documentaries and sharing various factoids she's learned with her colleagues.", "As a geneticist, Camille dislikes many popular sci-fi movies because they often present audiences with factoids that misrepresent her field." ]
1
closed choice
grade9
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be more commonly used, many people consider a word's traditional definition to be the correct usage. Being able to distinguish the different uses of a word can help you use it appropriately for different audiences. Britney perused her notes, carefully preparing for her exam. The traditional usage above is considered more standard. David perused the magazine, absentmindedly flipping through the pages. The nontraditional usage above is now commonly used, but traditional style guides generally advise against it.
The first text uses factoid in its traditional sense: something made up presented as a true fact. As a geneticist, Camille dislikes many popular sci-fi movies because they often present audiences with factoids that misrepresent her field. The second text uses factoid in its nontraditional sense: a trivial but true fact. As a geneticist, Camille enjoys watching science documentaries and sharing various factoids she's learned with her colleagues. Most style guides recommend to use the traditional sense of the word factoid because it is considered more standard.
Which correctly shows the title of a movie?
[ "***Max Keeble's Big Move***", "\"Max Keeble's Big Move\"" ]
0
closed choice
grade6
language science
punctuation
Formatting
Formatting titles
The title of a book, movie, play, TV show, magazine, or newspaper should be in italics. If you write it by hand, it can be underlined instead. A Midsummer Night's Dream The title of a poem, song, article, or short story should be in quotation marks. "You Are My Sunshine"
A movie should be in italics. The correct title is **Max Keeble's Big Move**.
Which closing is correct for a letter?
[ "Best Wishes,\nBrenda", "Best wishes,\nBrenda" ]
1
closed choice
grade4
language science
punctuation
Formatting
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I see it, I think of you. With love, Rory
The second closing is correct: Its first word is capitalized, and it ends with a comma.
Using only these supplies, which question can Katy investigate with an experiment?
[ "Do candles with thick wicks or with thin wicks produce more smoke?", "Do scented candles or unscented candles produce more smoke?", "Do large candles or small candles produce more smoke?" ]
0
Katy is burning some new candles. She notices that they produce different amounts of smoke. She wonders what factors affect how much smoke a candle produces. So, she decides to design an experiment. She has the following supplies available: two large unscented candles with thick wicks two large unscented candles with thin wicks a box of matches
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Which text message is more formal?
[ "Heads up! Benton is here. In the lobby.", "Ms. Benton is already here. She's waiting in the lobby." ]
1
closed choice
grade11
language science
writing-strategies
Audience, purpose, and tone
Which text is most formal?
Informal writing is typically used in casual situations or when communicating with someone you know well. Informal language often expresses familiarity and tends to sound more like speech. It uses more conversational language, such as slang, idioms, abbreviations, imprecise language, and contractions. Formal writing is typically used in academic and business writing or when writing directly to an authority figure. It tends to be more courteous and impersonal, avoiding overly familiar or conversational language. Compare the following sentences. Informal: Yeah, ostriches can't fly, but I think they're awesome. More formal: Ostriches may be flightless, but they're remarkable runners. Most formal: Though flightless, ostriches are remarkable runners.
The second text message is more formal. It uses complete sentences, avoids slang (heads up), and uses the person's title (Ms. Benton). The other text message includes more casual language and sentence fragments.
Select the one animal that has all of the amphibian traits listed above.
[ "American green tree frogs have moist, smooth skin and lay eggs with no shells. They live underwater for the first part of their lives. As adults, they live on land near ponds or swamps. Adult male American green tree frogs have a loud mating call.", "Chinese alligators live in lakes and streams in eastern China. They lay eggs with shells and live in underground burrows in the winter. Chinese alligators have scaly, waterproof skin." ]
0
Amphibians are a group of animals with similar traits. The following traits can be used to identify amphibians: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Amphibians have the following traits: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A Chinese alligator has the following traits: It has scaly, waterproof skin. It makes eggs with shells. A Chinese alligator does not have all of the traits of an amphibian. A Chinese alligator is a reptile. A green tree frog has the following traits: It spends part of its life in water and part on land. It has moist skin. It makes eggs with no shells. A green tree frog has the traits of an amphibian. A green tree frog is an amphibian.
Select the animal that does not have a backbone.
[ "redback spider", "carp" ]
0
Hint: Insects, spiders, and worms do not have backbones.
closed choice
grade2
natural science
biology
Classification
Identify animals with and without backbones
Some animals have a backbone. The backbone is made of many bones in an animal's back. An animal's backbone helps connect the different parts of its body. In the drawings below, each animal's backbone is colored orange. Other animals do not have a backbone. In fact, these animals don't have any bones! Some animals without backbones have a hard outer cover. Other animals have a soft body.
Like other spiders, a redback spider does not have a backbone. It has a hard outer cover. A carp is a fish. Like other fish, a carp has a backbone.
What do these two changes have in common? roasting a marshmallow over a campfire baking a loaf of bread
[ "Both are only physical changes.", "Both are caused by cooling.", "Both are chemical changes." ]
2
closed choice
grade7
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. As paper burns, paper molecules react with oxygen molecules in the air. This reaction breaks the chemical bonds in the molecules. The atoms then link together in a different way to form different molecules. For example, carbon dioxide molecules are formed when paper burns. In a physical change, chemical bonds do not break. The types of molecules in matter before and after a physical change are always the same. A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, water vaporizing is a physical change that can be caused by heating. Liquid water and water vapor are made of the same type of matter: water. The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change.
Step 1: Think about each change. Roasting a marshmallow is a chemical change. The type of matter on the outside of the marshmallow changes. As a marshmallow is roasted, it turns brown and crispy. Baking a loaf of bread is a chemical change. The type of matter in the dough changes when it is baked. The dough turns into bread! Step 2: Look at each answer choice. Both are only physical changes. Both changes are chemical changes. They are not physical changes. Both are chemical changes. Both changes are chemical changes. The type of matter before and after each change is different. Both are caused by heating. Both changes are caused by heating. Both are caused by cooling. Neither change is caused by cooling.
Is there a surplus or a shortage of posters?
[ "shortage", "surplus" ]
1
A poster company printed up 100 posters with its latest design. Posters cost $15 each. At that price, there are 80 people who want to buy one.
closed choice
grade5
social science
economics
Supply and demand
Identify shortage and surplus
There is a surplus if there is too much for sale at a given price. There is a shortage if there is not enough for sale at a given price. Surpluses and shortages usually happen when people who are selling goods or services charge too much or too little. When the price is too high, consumers will not want to buy much of the good or service. The quantity demanded will be less than the quantity supplied. So, there will be a surplus. When the price is too low, too many consumers will want to buy the good or service. The quantity demanded will be more than the quantity supplied. So, there will be a shortage.
At the current price, there are too many posters for sale. There are 100 posters for sale, but only 80 people want to buy one. So, there is a surplus of posters. The poster company will not get any money for the leftover posters.
Which word would you find on a dictionary page with the following guide words? battle - bluff
[ "behalf", "brow" ]
0
closed choice
grade7
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since behalf is between the guide words battle - bluff, it would be found on that page.
Select the one animal that has all of the reptile traits listed above.
[ "American green tree frogs have moist, smooth skin and lay eggs with no shells. They live underwater for the first part of their lives. As adults, they live on land near ponds or swamps. Adult male American green tree frogs have a loud mating call.", "Cobras hatch from eggs with shells. They have a wide, flat hood. A cobra can display its hood to scare away a predator. Like the rest of its body, the hood is covered in waterproof scales." ]
1
Reptiles are a group of animals with similar traits. The following traits can be used to identify reptiles: They have scaly, waterproof skin. They make eggs with shells. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Reptiles have the following traits: They have scaly, waterproof skin. They make eggs with shells. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A green tree frog has the following traits: It spends part of its life in water and part on land. It has moist skin. It makes eggs with no shells. A green tree frog does not have all of the traits of a reptile. A green tree frog is an amphibian. A cobra has the following traits: It has scaly, waterproof skin. It makes eggs with shells. A cobra has the traits of a reptile. A cobra is a reptile.
Which word would you find on a dictionary page with the following guide words? rat - rigid
[ "rehearse", "roast" ]
0
closed choice
grade5
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since rehearse is between the guide words rat - rigid, it would be found on that page.
What information supports the conclusion that Doug inherited this trait?
[ "Doug's parents were born with straight hair. They passed down this trait to Doug.", "Doug and his father both have short hair." ]
0
Read the description of a trait. Doug has straight hair.
closed choice
grade6
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring.
Is the following trait inherited or acquired? Maura has naturally red hair.
[ "inherited", "acquired" ]
0
Hint: Some people dye their hair. But this does not change their natural hair color.
closed choice
grade4
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
Humans do not choose their natural hair color. Instead, children get their natural hair color from their parents. So, Maura's hair color is an inherited trait.
Which logical fallacy is used in the text? I'm never setting foot in any seafood restaurant again. We just had a ridiculously overpriced dinner at Max's Seafood Hut, and I have no interest in repeating that experience.
[ "circular reasoning: an argument that supports a claim with the claim itself", "hasty generalization: a very broad claim based on very little evidence" ]
1
closed choice
grade8
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | a personal attack meant to discredit one's opponent appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something red herring | the use of a completely unrelated topic in support of a claim A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a very broad claim based on very little evidence straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that all seafood restaurants are overpriced. However, even though one seafood restaurant was overpriced, that doesn't necessarily mean that all seafood restaurants are overpriced. This illustrates a type of logical fallacy known as a hasty generalization.
Which closing is correct for a letter?
[ "Best regards,\nBen", "Best Regards,\nBen" ]
0
closed choice
grade2
language science
capitalization
Capitalization
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I see it, I think of you. With love, Rory
The second closing is correct: Its first word is capitalized, and it ends with a comma.
Would you find the word crystal on a dictionary page with the following guide words? carrot - congress
[ "yes", "no" ]
1
yes or no
grade6
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since crystal is not between the guide words carrot - congress, it would not be found on that page.
Which object has the most thermal energy?
[ "a metal paper clip at a temperature of 81°F", "a metal paper clip at a temperature of 89°F", "a metal paper clip at a temperature of 90°F" ]
2
The objects are identical except for their temperatures.
closed choice
grade4
natural science
physics
Heat and thermal energy
How is temperature related to thermal energy?
All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy. Temperature measures how hot or cold matter is. If the particles in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature.
All three metal paper clips have the same mass but different temperatures. Since the 90°F paper clip is the hottest, it has the most thermal energy.
Which is a complete sentence?
[ "The cook always wears an apron.", "Will change out of her wet pants and shirt." ]
0
closed choice
grade3
language science
writing-strategies
Sentences, fragments, and run-ons
Is it a complete sentence, a fragment, or a run-on?
A sentence is a group of words that forms a complete thought. It has both a subject and a verb. My friends walk along the path. A sentence fragment is a group of words that does not express a complete thought. It is usually missing a subject or a verb. Knows the answer. This is a sentence fragment. It is missing a subject. Who knows the answer? She knows the answer. The bright red car. This is a sentence fragment. It is missing a verb. What did the bright red car do? The bright red car stopped. A run-on sentence is made up of two sentences that are joined without end punctuation or with just a comma. I knocked on the door it opened. It started raining, we ran inside. To fix a run-on sentence, separate it into two sentences. Add end punctuation after the first sentence, and capitalize the second sentence. I knocked on the door. It opened. It started raining. We ran inside. You can also fix a run-on sentence by rewriting it as a compound sentence. A compound sentence is two sentences joined by a comma and a conjunction such as and, but, or, or so. I knocked on the door, and it opened. It started raining, so we ran inside.
The cook always wears an apron is a complete sentence. The subject is the cook, and the verb is wears.
Compare the motion of three bicycles. Which bicycle was moving at the highest speed?
[ "a bicycle that moved 130miles west in 10hours", "a bicycle that moved 55miles north in 10hours", "a bicycle that moved 170miles west in 10hours" ]
2
closed choice
grade3
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the mile. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about objects moving for the same amount of time. The object that is moving the fastest will go the farthest distance in that time. It is moving at the highest speed.
Look at the distance each bicycle moved and the time it took to move that distance. The direction each bicycle moved does not affect its speed. Notice that each bicycle moved for 10 hours. The bicycle that moved 170 miles moved the farthest distance in that time. So, that bicycle must have moved at the highest speed.
Would you find the word down on a dictionary page with the following guide words? dandy - dirty
[ "no", "yes" ]
0
yes or no
grade8
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since down is not between the guide words dandy - dirty, it would not be found on that page.
Is the following trait inherited or acquired? Lena can ride a motorcycle.
[ "inherited", "acquired" ]
1
Hint: Riding a motorcycle well takes practice.
closed choice
grade3
natural science
biology
Heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
People are not born knowing how to ride a motorcycle. Instead, many people learn how to ride. So, riding a motorcycle is an acquired trait.
Select the living thing.
[ "echidna", "flower pot" ]
0
closed choice
grade3
natural science
biology
Classification
Identify living and nonliving things
All living things need food and water. Water helps living things break down food and remove waste. Food gives living things energy. Living things use this energy to grow and change. All living things grow and change during their lives. All living things sense changes in the world around them. Living things might sense changes by seeing, smelling, hearing, or feeling. Living things can respond to the changes they sense.
An echidna is a living thing. Echidnas grow and respond to the world around them. They need food and water. Echidnas are mammals. Most mammals give birth to live young, but echidnas lay eggs! Egg-laying mammals are called monotremes. A flower pot is not a living thing. Flower pots do not have all of the traits of living things. They do not grow or respond to the world around them. They do not need food or water.
Which greeting is correct for a letter?
[ "Dear Aunt Kate,", "dear Aunt Kate," ]
0
closed choice
grade2
language science
capitalization
Capitalization
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I see it, I think of you. With love, Rory
The second greeting is correct: Its first word is capitalized, and it ends with a comma. Aunt Kate is capitalized because it is a proper noun.
What does the idiom in this text suggest? Mr. and Mrs. Underwood usually see eye to eye, but not when it comes to the controversial mayoral race.
[ "Mr. and Mrs. Underwood look each other in the eye.", "Mr. and Mrs. Underwood usually agree." ]
1
closed choice
grade10
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. An idiom is an expression that cannot be understood literally. Its meaning must be learned. The assignment was a piece of cake.
The text uses an idiom, an expression that cannot be understood literally. The idiom see eye to eye suggests that Mr. and Mrs. Underwood usually agree. When you see eye to eye with someone, you share their opinion.
Using only these supplies, which question can Scott investigate with an experiment?
[ "Do cloth towels dry faster if they are hung in the laundry room or in the backyard?", "Does a small cloth towel or a large cloth towel dry faster when hung in the backyard?", "When hung in the laundry room, do black cloth towels or white cloth towels dry more quickly?" ]
0
After Scott cleans up a spill, he hangs a wet cloth towel in the laundry room. Two hours later, he notices that the towel has partially dried. He wonders what factors affect how cloth dries. So, he decides to design an experiment. He has the following supplies available: two identical white cloth towels water a clothesline in the laundry room a clothesline in the backyard
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Which figure of speech is used in this text? You've reached Peter Sawyer's voice mail. Please leave a detailed message at the beep, and I will return your call at my earliest convenience.
[ "onomatopoeia", "idiom" ]
0
closed choice
grade7
language science
figurative-language
Literary devices
Classify figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Alliteration is the repetition of sounds at the beginning of nearby words. What a lucky little lady you are! An allusion is a brief reference to something or someone well known, often from history or literature. "I'd better get home before I turn into a pumpkin!" Lila remarked. An idiom is an expression that cannot be understood literally. Its meaning must be learned. The assignment was a piece of cake. A simile uses like or as to compare two things that are not actually alike. The cat's fur was as dark as the night. A metaphor compares two things that are not actually alike without using like or as. The snow formed a blanket over the town. Onomatopoeia involves using a word that expresses a sound. The scrambled eggs hit the floor with a splat. Personification is giving human characteristics to nonhuman things. The trees danced in the wind. A pun involves using a word or phrase in a humorous way that suggests more than one meaning. A great new broom is sweeping the nation. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking down. Each breakdown is as enjoyable as a punch to the face.
The text uses onomatopoeia, a word that expresses a sound. Beep represents the sound that tells the caller to start recording a message.
Which bowl of cereal has more thermal energy?
[ "the colder bowl of cereal", "the hotter bowl of cereal" ]
1
Two bowls of cereal are identical except for their temperatures.
closed choice
grade6
natural science
physics
Thermal energy
How are temperature and mass related to thermal energy?
Matter is made of tiny particles called atoms. Atoms are always moving. The energy of moving atoms is called thermal energy. The total amount of thermal energy in matter depends on three things: the type of matter, the amount of matter, and how fast the atoms are moving. Temperature measures how hot or cold matter is. If the atoms in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature. What happens if the amount of matter changes? A 2-kilogram brick at 70°F has twice as much thermal energy as a 1-kilogram brick at 70°F. The two bricks have the same temperature, but the larger brick has twice as many atoms. So, it has twice as much thermal energy.
The two bowls of cereal are made of the same material and have the same mass. So, the hotter bowl of cereal has more thermal energy.
Compare the motion of two birds. Which bird was moving at a lower speed?
[ "a bird that moved 30kilometers in 5hours", "a bird that moved 45kilometers in 5hours" ]
0
closed choice
grade2
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the kilometer. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about two objects moving for the same amount of time. The object that is moving slower will go a shorter distance in that time. It is moving at a lower speed.
Look at the distance each bird moved and the time it took to move that distance. One bird moved 30 kilometers in 5 hours. The other bird moved 45 kilometers in 5 hours. Notice that each bird spent the same amount of time moving. The bird that moved 30 kilometers moved a shorter distance in that time. So, that bird must have moved at a lower speed.
Which type of sentence is this? As Mike sat down on the rickety old chair, it abruptly collapsed beneath him.
[ "compound", "simple", "compound-complex", "complex" ]
3
closed choice
grade12
language science
grammar
Phrases and clauses
Is the sentence simple, compound, complex, or compound-complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought that can stand alone as a sentence. A dependent clause (or subordinate clause) is not a complete thought and cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alone. It is independent. after we pick up Kevin from work The clause cannot stand alone. It is dependent. A simple sentence is made up of a single independent clause. Ben and I spent all day relaxing by the pool. Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate. In the winter, Ben usually wears his heavy coat. Ben usually wears his heavy coat in the winter. A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so. We saw the flash of lightning, and seconds later we heard a rumble of thunder. A complex sentence is made up of an independent clause and a dependent clause. The dependent clause in a complex sentence usually begins with a subordinating conjunction or relative pronoun. Subordinating conjunctions include after, although, as, because, before, if, since, unless, until, when, and while. Relative pronouns include that, which, who, whom, or whose. If she ever gets the chance, Terri would love to visit the Egyptian pyramids. During his trip to Italy, Tony visited the Trevi Fountain, which is in Rome. A compound-complex sentence is made up of two or more independent clauses and one or more dependent clauses. After Samantha left work, she stopped at the bank, and then she went to the gym. Sometimes a dependent clause in a complex or compound-complex sentence can interrupt an independent clause. Orcas that are kept in captivity often have bent dorsal fins.
The sentence is complex. It is made up of an independent clause and a dependent clause. The dependent clause begins with the subordinating conjunction as. As Mike sat down on the rickety old chair, it abruptly collapsed beneath him.
Which correctly shows the title of a book?
[ "The Blue Cat of Castle Town", "the Blue Cat of Castle Town" ]
0
closed choice
grade2
language science
capitalization
Capitalization
Capitalizing titles
In a title, capitalize the first word, the last word, and every important word in between. The Wind in the Willows James and the Giant Peach These words are not important in titles: Articles, a, an, the Short prepositions, such as at, by, for, in, of, on, to, up Coordinating conjunctions, such as and, but, or
Capitalize the first word, the last word, and every important word in between. The word of is not important, so it should not be capitalized. The correct title is The Blue Cat of Castle Town.
How long does it take for an airplane to cross the Atlantic Ocean?
[ "6 seconds", "6 hours" ]
1
Select the better estimate.
closed choice
grade3
natural science
units-and-measurement
Units and measurement
Choose units of time
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Imagine being told that the bus leaves in 7. You might be thinking, 7 what? Does the bus leave in 7 minutes? 7 seconds? The number 7 on its own does not give you much information about when the bus is leaving. That is because the units are missing. Time is usually measured in units of seconds, minutes, or hours. It takes about 1 second to sneeze and 1 minute to get dressed in the morning. It takes about 1 hour to bake a pie in the oven. There are 60 seconds in 1 minute. So, 1 second is much less than 1 minute. There are 60 minutes in 1 hour. So, 1 minute is much less than 1 hour.
The better estimate for how long it takes for an airplane to cross the Atlantic Ocean is 6 hours. 6 seconds is too fast.
Which greeting is correct for a letter?
[ "Dear Grandma Emily,", "dear Grandma Emily," ]
0
closed choice
grade2
language science
capitalization
Capitalization
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I see it, I think of you. With love, Rory
The first greeting is correct: Its first word is capitalized, and it ends with a comma. Grandma Emily is capitalized because it is a proper noun.
Select the living thing.
[ "mango tree", "brick wall" ]
0
closed choice
grade3
natural science
biology
Classification
Identify living and nonliving things
All living things need food and water. Water helps living things break down food and remove waste. Food gives living things energy. Living things use this energy to grow and change. All living things grow and change during their lives. All living things sense changes in the world around them. Living things might sense changes by seeing, smelling, hearing, or feeling. Living things can respond to the changes they sense.
A brick wall is not a living thing. Brick walls do not have all of the traits of living things. They do not grow or respond to the world around them. They do not need food or water. A mango tree is a living thing. Mango trees grow and respond to the world around them. They need food and water. Mango trees are plants. They make their own food using water, carbon dioxide, and energy from sunlight.
Suppose Kaylee decides to go as a superhero. Which result would be a cost?
[ "Kaylee will save some time and money. She won't have to go out and get a new costume.", "Kaylee will give up the chance to wear the costume she is more excited about." ]
1
Kaylee is deciding whether to go as a vampire or a superhero to a costume party. She would rather go as a vampire. But she already has a superhero costume.
closed choice
grade4
social science
economics
Basic economic principles
Costs and benefits
Before you decide to do something, it is often helpful to list costs and benefits. Costs are what you give up or spend when you decide to do something. Costs involve giving up things that you want or need. Benefits are what you gain or save when you decide to do something. Benefits involve gaining something that you want or need.
This result is a cost. It involves giving up or spending something that Kaylee wants or needs: Kaylee will give up the chance to wear the costume she is more excited about.
Complete the sentence so that it uses personification. Summer () this year; I'm not ready for it to be this hot!
[ "came early", "sneaked up on me" ]
1
closed choice
grade10
language science
writing-strategies
Creative techniques
Use personification
Personification is giving human characteristics to nonhuman things. It is a figure of speech that can be used to make writing more interesting or to emphasize a point. The trees danced in the wind. The word danced describes the trees as if they were people. Unlike people, however, trees can't actually dance. Instead, the personification suggests that the trees are moving.
Complete the sentence with the phrase sneaked up on me. It describes summer as if it were a sneaky person.
Complete the statement. Hydrogen bromide is ().
[ "an elementary substance", "a compound" ]
1
Hydrogen bromide can be used to speed up certain types of chemical reactions. The chemical formula for hydrogen bromide is HBr.
closed choice
grade8
natural science
chemistry
Atoms and molecules
Classify elementary substances and compounds using chemical formulas
There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you. A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are composed of multiple chemical elements bonded together are compounds. Every chemical element is represented by its own atomic symbol. An atomic symbol may consist of one capital letter, or it may consist of a capital letter followed by a lowercase letter. For example, the atomic symbol for the chemical element fluorine is F, and the atomic symbol for the chemical element beryllium is Be. The atomic symbol for each chemical element in a substance is shown in the substance's chemical formula. An elementary substance is represented by a chemical formula that contains only one atomic symbol. The atomic symbol in a chemical formula may be followed by a small number written lower than the symbol. This number is called a subscript. A subscript is included when the atoms in the elementary substance are bonded to form molecules. The subscript shows how many atoms are in each molecule. For example, the chemical formula for the elementary substance oxygen, O2, has a subscript of 2. This subscript shows that the atomic symbol O represents two atoms. The elementary substance O2 and the chemical element represented by the atomic symbol O are both named oxygen. So, the formula tells you that each molecule of O2 contains two oxygen atoms. A compound is represented by a chemical formula that contains multiple atomic symbols. The chemical elements in a compound are bonded together in a fixed ratio. This ratio is shown in a compound's chemical formula. For example, in the compound beryllium fluoride, there is one beryllium atom for every two fluorine atoms. So, the ratio of beryllium atoms to fluorine atoms is 1 to 2. This ratio is shown in the chemical formula for beryllium fluoride, BeF2. There is no subscript following the atomic symbol Be because that symbol represents one atom. The subscript 2 follows the atomic symbol F to show that the symbol represents two atoms.
You can tell whether hydrogen bromide is an elementary substance or a compound by counting the number of atomic symbols in its chemical formula. An atomic symbol consists of either one capital letter or a capital letter followed by one or two lowercase letters. The chemical formula for hydrogen bromide, HBr, contains two atomic symbols: H for hydrogen and Br for bromine. So, the formula tells you that hydrogen bromide is composed of two chemical elements bonded together. Since hydrogen bromide is composed of multiple chemical elements bonded together, hydrogen bromide is a compound.
Which phrase has a more positive connotation?
[ "searching for something", "snooping for something" ]
0
closed choice
grade4
language science
vocabulary
Shades of meaning
Positive and negative connotation
Connotation is the feeling or idea that goes along with a word or phrase. Some words are close in meaning but have different connotations. For example, think about the words eager and impatient. They both mean wanting something to happen, but they have different connotations. Eager has a positive connotation. It is a nice word. An eager person is happy and excited. Impatient has a negative connotation. It is not a nice word. An impatient person is often pushy and demanding.
Searching for something has a more positive connotation. Searching is looking for something carefully. Snooping is looking for something without permission.
Using only these supplies, which question can Ann investigate with an experiment?
[ "When placed in the sun, will eight ounces of water in a closed jar or eight ounces of water in an open jar get warmer?", "Will eight ounces of carbonated water or eight ounces of tap water get warmer when placed in a jar in the sun?", "When placed in the sun, will eight ounces of water in a glass jar or eight ounces of water in a plastic cup get warmer?" ]
0
Ann leaves a glass jar of cold tea outside in full sunlight. When she goes to get it, she notices that the tea is warm. She wonders what factors affect how warm a liquid gets from sitting in the sunlight. So, she decides to design an experiment. She has the following supplies available: two identical glass jars two jar lids tap water a measuring cup two thermometers
closed choice
grade7
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Which logical fallacy is used in the text? Jimi Hendrix, Janis Joplin, Jim Morrison, Kurt Cobain, and Amy Winehouse all passed away at the age of twenty-seven. For some reason, being twenty-seven seems to be dangerous for musicians.
[ "hasty generalization: a broad claim based on too few observations", "slippery slope fallacy: the false assumption that a small first step will lead to extreme consequences", "appeal to nature: the assumption that natural things are always good" ]
0
closed choice
grade12
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | an attack against the person making the argument, rather than the argument itself appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a broad claim based on too few observations slippery slope fallacy | the false assumption that a small first step will necessarily lead to extreme consequences straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that being twenty-seven makes musicians more likely to pass away. However, that's not necessarily true. These tragedies are likely a coincidence. This illustrates a type of logical fallacy known as a hasty generalization.