A: S=60k/d2 60;S=60/15  220 = 3/20 candles. The answer is (A).
Answer the following multiple choice question with options (a), (b), (c), (d), (e) by reasoning step-by-step.
Q:For a light that has an intensity of 60 candles at its source, the intensity in candles, S, of the light at a point d d feet from the source is given by the formula S=60k/d^2 60, where k is a constant. If the intensity of the light is 15 candles at a distance of 2 feet from the source, what is the intensity of the light at a distance of 20 feet from the source? Answer Choices: A)3/20 candles B)1/2 candles C)1 1/3 candles D)2 candles E)3 candles