Task: Question Answering
Input (English): Problem: two trains of equal are running on parallel lines in the same direction at 42 km / hr and 36 km / hr . the faster train passes the slower train in 36 sec . the length of each train is ? 
Options: a ) 30 m , b ) 72 m , c ) 80 m , d ) 82 m , e ) 84 m
Output (English): a