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 copy machine , working at a constant rate , makes 40 copies per minute . a second copy machine , working at a constant rate , makes 55 copies per minute . working together at their respective rates , how many copies do the two machines make in half an hour ? 
Options: a ) 90 , b ) 2,700 , c ) 4,500 , d ) 5,400 , e ) 2,850

Ex Output:
e


Ex Input:
Problem: a train is 300 meter long is running at a speed of 35 km / hour . in what time will it pass a bridge of 115 meter length ? 
Options: a ) 29 , b ) 23 , c ) 47.119 , d ) 44.586 , e ) 42.686

Ex Output:
e


Ex Input:
Problem: how many seconds will a train 200 meters long running at the rate of 36 kmph take to pass a certain telegraph post ? 
Options: a ) 10 sec , b ) 20 sec , c ) 25 sec , d ) 30 sec , e ) 35 sec

Ex Output:

b