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: due to construction , the speed limit along an 5 - mile section of highway is reduced from 52 miles per hour to 36 miles per hour . approximately how many minutes more will it take to travel along this section of highway at the new speed limit than it would have taken at the old speed limit ? 
Options: a ) a ) 3.12 , b ) b ) 8 , c ) c ) 10 , d ) d ) 2.57 , e ) e ) 24
Example Output: d

Example Input: Problem: there are two cars . one is 60 miles north of the other . simultaneously , the car to the north is driven westward at 15 miles per hour and the other car is driven eastward at 25 miles per hour . how many miles apart are the cars after 2 hours ? 
Options: a ) 60 , b ) 80 , c ) 100 , d ) 120 , e ) 140
Example Output: c

Example Input: Problem: a can do a work in 21 days and b alone can do it 28 days , they begin the work together , but a left after some days . b completed the remaining work in 21 days . after how many days did a leave ? 
Options: a ) 10 , b ) 8 , c ) 3 , d ) 15 , e ) 16
Example Output:
c