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: two pipes a and b can separately fill a tank in 12 and 20 minutes respectively . a third pipe c can drain off 45 liters of water per minute . if all the pipes are opened , the tank can be filled in 15 minutes . what is the capacity of the tank ? 
Options: a ) 542 , b ) 540 , c ) 675 , d ) 829 , e ) 279

Output: c


Input: Consider Input: Problem: edward earns $ 7.00 per hour for the first 40 hours he works per week , and twice this rate for overtime . if michael earned $ 210 last week , how many hours did he work ? 
Options: a ) 43 , b ) 44 , c ) 45 , d ) 46 , e ) 47

Output: c


Input: Consider Input: Problem: a can do a piece of work in 80 days . he works at it for 10 days & then b alone finishes the remaining work in 42 days . in how much time will a and b , working together , finish the work ? 
Options: a ) 30 days , b ) 20 days , c ) 25 days , d ) 35 days , e ) 45 days


Output: a