Task: Question Answering
Input (English): Problem: two good train 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 ) 12 sec , b ) 24 sec , c ) 48 sec , d ) 72 sec , e ) none
Output (English): d