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 river boat leaves silver town and travels upstream to gold town at an average speed of 3 kilometers per hour . it returns by the same route at an average speed of 7 kilometers per hour . what is the average speed for the round - trip in kilometers per hour ? 
Options: a ) 4.2 , b ) 7.1 , c ) 7.2 , d ) 7.5 , e ) 8.0

Ex Output:
a


Ex Input:
Problem: in what time will a railway train 110 m long moving at the rate of 36 kmph pass a telegraph post on its way ? 
Options: a ) 6 sec , b ) 7 sec , c ) 8 sec , d ) 11 sec , e ) 2 sec

Ex Output:
d


Ex Input:
Problem: the diameter of a garden roller is 1.2 m and it is 2 m long . how much area will it cover in 5 revolutions ? ( use ï € = 22 â  „ 7 ) 
Options: ['a ) 40 m 2', 'b ) 44 m 2', 'c ) 48 m 2', 'd ) 37.7 m 2', 'e ) none of these']

Ex Output:

d