Task: Question Answering
Input (English): Problem: two goods trains each 750 m long are running in opposite directions on parallel tracks . their speeds are 45 km / hr and 30 km / hr respectively . find the time taken by the slower train to pass the driver of the faster one ? 
Options: a ) 72 , b ) 45 , c ) 48 , d ) 51 , e ) 44
Output (English): a