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'.

Input: Consider Input: Problem: if 36 men can do a piece of work in 5 hours , in how many hours will 15 men do it ? 
Options: a ) 12 , b ) 38 , c ) 60 , d ) 88 , e ) 72

Output: a


Input: Consider Input: Problem: the distance between west - town to east - town is 20 kilometers . two birds start flying simultaneously towards one another , the first leaving from west - town at a speed of 4 kilometers per minute and the second bird , leaving from east - town , at a speed of 1 kilometers per minute . what will be the distance , in kilometers , between the meeting point and west - town ? 
Options: a ) 3 . , b ) 7 . , c ) 10 . , d ) 16 . , e ) 15 .

Output: d


Input: Consider Input: Problem: a and b complete a work in 10 days . a alone can do it in 14 days . if both together can do the work in how many days ? 
Options: a ) 5.8 days , b ) 4.78 days , c ) 6.25 days , d ) 3.15 days , e ) 2.75 days


Output: a