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: the sum of 4 consecutive even numbers is 140 . what would be the smallest number ? 
Options: a ) 32 , b ) 88 , c ) 70 , d ) 123 , e ) 12
Example Output: a

Example Input: Problem: joe needs to paint all the airplane hangars at the airport , so he buys 360 gallons of paint to do the job . during the first week , he uses 1 / 4 of all the paint . during the second week , he uses 1 / 4 of the remaining paint . how many gallons of paint has joe used ? 
Options: a ) 18 , b ) 157 , c ) 175 , d ) 216 , e ) 250
Example Output: b

Example Input: Problem: a cistern which could be filled in 10 hours takes 2 hour more to be filled owing to a leak in its bottom . if the cistern is full , in what time will the leak empty it ? 
Options: a ) 50 hours , b ) 80 hours , c ) 100 hours , d ) 150 hours , e ) 110 hours
Example Output:
e