In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: express 35 mps in kmph ? 
Options: a ) 122 , b ) 188 , c ) 126 , d ) 140 , e ) 124

Ex Output:
c


Ex Input:
Problem: a man started driving at a constant speed , from the site of a blast , the moment he heard the blast . he heard a second blast after a time of 30 mins and 12 seconds . if the second blast occurred exactly 30 mins after the first , how many meters was he from the site when he heard the second blast ? ( speed of sound = 330 m / s ) 
Options: a ) 3120 , b ) 3330 , c ) 3540 , d ) 3750 , e ) 3960

Ex Output:
e


Ex Input:
Problem: two passenger trains start at the same hour in the day from two different stations and move towards each other at the rate of 13 kmph and 21 kmph respectively . when they meet , it is found that one train has traveled 60 km more than the other one . the distance between the two stations is ? 
Options: a ) 11 , b ) 408 , c ) 2881 , d ) 287 , e ) 221

Ex Output:

b