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'.

Q: Problem: two consultants can type up a report in 12.5 hours and edit it in 7.5 hours . if mary needs 30 hours to type the report and jim needs 12 hours to edit it alone , how many t hours will it take if jim types the report and mary edits it immediately after he is done ? 
Options: a ) 41.4 , b ) 34.1 , c ) 13.4 , d ) 12.4 , e ) 10.8

A: a
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Q: 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

A: a
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Q: Problem: 3 pumps , working 8 hours a day , can empty a tank in 2 days . how many hours a day must 6 pumps work to empty the tank in 1 day ? 
Options: a ) 8 , b ) 10 , c ) 11 , d ) 12 , e ) 13

A:
a
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