In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: if a certain computer is capable of printing 4700 monthly credit card bills per hour , while a new model is capable of printing at a rate of 6800 per hour , the old model will take approximately how much longer than the new model to print 10000 bills ? 
Options: a ) 19 mins , b ) 29 mins , c ) 39 mins , d ) 38 mins , e ) 37 mins

Ex Output:
c


Ex Input:
Problem: if the sales tax reduced from 3 1 / 2 % to 3 1 / 3 % , then what difference does it make to a person who purchases an article with market price of rs . 10800 ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 18 , e ) 10

Ex Output:
d


Ex Input:
Problem: a man has some hens and cows . if the number of heads be 100 and the number of feet equals 180 , then the number of hens will be : 
Options: a ) 22 , b ) 23 , c ) 80 , d ) 90 , e ) 28

Ex Output:

d