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: a and b can do a piece of work in 8 days . with the help of c they finish the work in 4 days . c alone can do that piece of work in ? 
Options: a ) 40 days , b ) 20 days , c ) 8 days , d ) 60 days , e ) 40 days

Answer: c


Question: 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

Answer: a


Question: Problem: a train is moving at 6 / 7 of its usual speed . the train is 10 minutes too late . what is the usual time ( in hours ) for the train to complete the journey ? 
Options: a ) 0.5 , b ) 1 , c ) 1.5 , d ) 2 , e ) 2.5

Answer:
b