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: a man can row upstream at 26 kmph and downstream at 30 kmph , and then find the speed of the man in still water ? 
Options: a ) 29 , b ) 28 , c ) 30 , d ) 32 , e ) 23

A: b
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Q: Problem: two trains of equal length are running on parallel lines in the same direction at 46 km / hr and 36 km / hr . the faster train catches and completely passes the slower train in 54 seconds . what is the length of each train ( in meters ) ? 
Options: a ) 45 , b ) 55 , c ) 65 , d ) 75 , e ) 85

A: d
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Q: Problem: 2 men and 4 boys can complete a work in 4 days . 5 men and 6 boys can complete the same work in 3 days . the work done by 2 boys is equal to the work of how many men ? 
Options: a ) 4 , b ) 5 , c ) 6 , d ) 7 , e ) 8

A:
b
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