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: two trains are moving in opposite directions at 60 km / hr and 90 km / hr . their lengths are 2.9 km and 1.6 km respectively . the time taken by the slower train to cross the faster train in seconds is ? 
Options: a ) 99 , b ) 277 , c ) 48 , d ) 96 , e ) 108

Ex Output:
e


Ex Input:
Problem: a train is 485 meter long is running at a speed of 45 km / hour . in what time will it pass a bridge of 140 meter length 
Options: a ) 20 seconds , b ) 30 seconds , c ) 40 seconds , d ) 50 seconds , e ) none of these

Ex Output:
d


Ex Input:
Problem: there are 24 stations between ernakulam and chennai . how many second class tickets have to be printed , so that a passenger can travel from one station to any other station ? 
Options: a ) 800 , b ) 820 , c ) 650 , d ) 870 , e ) 900

Ex Output:

c