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: when working alone , painter w can paint a room in 2 hours , and working alone , painter x can paint the same room in h hours . when the two painters work together and independently , they can paint the room in 3 / 4 of an hour . what is the value of h ? 
Options: a ) 3 / 4 , b ) 1 [ 1 / 5 ] , c ) 1 [ 2 / 5 ] , d ) 1 [ 3 / 4 ] , e ) 2

A: b
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Q: Problem: dan can do a job alone in 15 hours . annie , working alone , can do the same job in just 10 hours . if dan works alone for 3 hours and then stops , how many hours will it take annie , working alone , to complete the job ? 
Options: a ) 2 , b ) 4 , c ) 6 , d ) 8 , e ) 10

A: d
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Q: Problem: a boat can travel with a speed of 24 km / hr in still water . if the speed of the stream is 4 km / hr , find the time taken by the boat to go 56 km downstream 
Options: a ) 2 hours , b ) 4 hours , c ) 5 hours , d ) 6 hours , e ) 7 hours

A:
a
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