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 train is 360 meter long is running at a speed of 30 km / hour . in what time will it pass a bridge of 140 meter length ? 
Options: a ) 87 , b ) 69 , c ) 60 , d ) 72 , e ) 21

Ex Output:
c


Ex Input:
Problem: a can finish a work in 12 days and b can do the same work in 15 days . b worked for 10 days and left the job . in how many days , a alone can finish the remaining work ? 
Options: a ) 4 , b ) 5 1 / 2 , c ) 6 , d ) 8 , e ) none of these

Ex Output:
a


Ex Input:
Problem: a train 150 m long passes a man , running at 5 km / hr in the same direction in which the train is going , in 10 seconds . the speed of the train is : 
Options: a ) 22 , b ) 50 , c ) 99 , d ) 288 , e ) 59

Ex Output:

e