Task: Question Answering
Input (English): Problem: two bullet train s 140 m and 210 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks . the time ( in seconds ) which they take to cross each other , is : 
Options: a ) 15.8 sec . , b ) 12.6 sec . , c ) 11.8 sec . , d ) 10.8 sec . , e ) 08.8 sec .
Output (English): b