Task: Question Answering
Input (English): Problem: the roof of an apartment building is rectangular and its length is 7 times longer than its width . if the area of the roof is 847 feet squared , what is the difference between the length and the width of the roof ? 
Options: a ) 38 . , b ) 40 . , c ) 66 . , d ) 44 . , e ) 46 .
Output (English): c