Task: Question Answering
Input (English): Problem: the speed at which a man can row a boat in still water is 15 km / hr . if he rows downstream , where the speed of current is 3 km / hr , how many seconds will he take to cover 90 meters ? 
Options: a ) 12 , b ) 16 , c ) 17 , d ) 18 , e ) 20
Output (English): d