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 14 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 ) 477 , b ) 420 , c ) 279 , d ) 276 , e ) 291
Example Output: b

Example Input: Problem: ram , who is half as efficient as krish , will take 27 days to complete a task if he worked alone . if ram and krish worked together , how long will they take to complete the task ? 
Options: a ) 16 days , b ) 12 days , c ) 9 days , d ) 6 days , e ) 18 days
Example Output: c

Example Input: Problem: a train 280 m long can cross an electric pole in 20 sec and then find the speed of the train ? 
Options: a ) 88 kmph , b ) 89 kmph , c ) 72 kmph , d ) 50 kmph , e ) 18 kmph
Example Output:
d