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 is twice as good a workman as b and together they complete a work in 12 days . in how many days a alone can do the work ?
Options: a ) 32 , b ) 33 , c ) 34 , d ) 35 , e ) 36

Ex Output:
e

Ex Input:
Problem: a bus 75 m long is running with a speed of 21 km / hr . in what time will it pass a woman who is walking at 3 km / hr in the direction opposite to that in which the bus is going ?
Options: a ) 5.75 , b ) 7.62 , c ) 11.25 , d ) 4.25 , e ) 3.25

Ex Output:
c

Ex Input:
Problem: x alone can do a piece of work in 15 days and y alone can do it in 10 days . x and y undertook to do it for rs . 720 . with the help of z they finished it in 5 days . how much is paid to z ?
Options: a ) rs . 360 , b ) rs . 120 , c ) rs . 240 , d ) rs . 300 , e ) none

Ex Output:
b