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: a train passes a station platform in 35 sec and a man standing on the platform in 20 sec . if the speed of the train is 54 km / hr . what is the length of the platform ? 
Options: a ) 228 , b ) 240 , c ) 225 , d ) 166 , e ) 1811

Ex Output:
c


Ex Input:
Problem: a man can row 8 kmph in still water . when the river is running at 1.2 kmph , it takes him 1 hour to row to a place and black . how far is the place ? 
Options: a ) 3.58 , b ) 3.68 , c ) 3.78 , d ) 3.88 , e ) 3.98

Ex Output:
b


Ex Input:
Problem: if in a race of 80 m , a covers the distance in 20 seconds and b in 25 seconds , then a beats b by : 
Options: a ) 16 m , b ) 18 m , c ) 15 m , d ) 14 m , e ) 11 m

Ex Output:

a