How many years after Baldwin de Burg became Count of Edessa did he become King Baldwin II of Jerusalem?
return Baldwin  de Burg became Count of Edessa ;return Baldwin  de Burg became King Baldwin II of Jerusalem ;return year of #1 ;return year of #2 ;return the  difference of #4 and  #3
['select', 'select', 'project', 'project', 'arithmetic']