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: if a man earns rs 20 on first day and spends rs 15 on second day , and earns rs 20 on third day and spends rs 15 on fourth day and goes on on which day he will be having rs 60 . 
Options: a ) 40 rs , b ) 45 rs , c ) 50 rs , d ) 55 rs , e ) 60 rs
Example Output: e

Example Input: Problem: two trains a and b are 125 m and 150 m long and are moving at one another at 54 km / hr and 36 km / hr respectively . arun is sitting on coach b 1 of train a . calculate the time taken by arun to completely cross train b . 
Options: a ) 10 s , b ) 11 s , c ) 4 s , d ) 8 s , e ) 12 s
Example Output: b

Example Input: Problem: a can run 2 km distance in 2 min 20 seconds , while b can run this distance in 3 min 5 sec . . by how much distance can a beat b ? 
Options: a ) 900 m , b ) 500 m , c ) 120 m , d ) 180 m , e ) 190 m
Example Output:
b