Task: Question Answering
Input (English): Problem: gary drove from point a to point b at 60 km / h . on his way back he took a train travelling at 110 km / h and therefore his trip back lasted 5 hours less . what is the distance ( in km ) between a and b ? 
Options: a ) 600 . , b ) 630 . , c ) 660 . , d ) 690 . , e ) 720 .
Output (English): c