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'.
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Question: Problem: if 8 men or 12 women can do a piece of work in 20 days , in how many days can the same work be done by 6 men and 11 women ? 
Options: a ) 10 days , b ) 11 days , c ) 12 days , d ) 15 days , e ) 17 days

Answer: c


Question: 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

Answer: c


Question: Problem: 20 beavers , working together in a constant pace , can build a dam in 3 hours . how many hours c will it take 12 beavers that work at the same pace , to build the same dam ? 
Options: a ) 2 . , b ) 4 . , c ) c = 5 . , d ) c = 6 . , e ) 8 .

Answer:
c