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'.

Example 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 24 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 ) 288 , b ) 540 , c ) 877 , d ) 278 , e ) 178
Example Output: b

Example Input: Problem: a and b finish the job in 15 days . while a , b and c can finish it in 11 days . c alone will finish the job in 
Options: a ) 41.25 days , b ) 30.25 days , c ) 60.25 days , d ) 71.25 days , e ) 51.25 days
Example Output: a

Example Input: Problem: a can do a work in 30 days , b can do it in 20 days . they together under took to do a piece of work for rs . 1000 , what is the share of b ? 
Options: a ) rs . 500 , b ) rs . 400 , c ) rs . 800 , d ) rs . 600 , e ) rs . 200
Example Output:
d