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 man can row downstream at 16 kmph and upstream at 10 kmph . find the speed of the man in still water and the speed of stream respectively ? 
Options: a ) 3 , b ) 5 , c ) 6 , d ) 4 , e ) 9

Answer: a


Question: Problem: a can do a piece of work in 4 hours ; b and c together can do it in 2 hours , while a and c together can do it in 2 hours . how long will b alone take to do it ? 
Options: a ) 12 , b ) 9 , c ) 8 , d ) 6 , e ) 4

Answer: e


Question: Problem: in a lake , there is a patch of lily pads . every day , the patch doubles in size . it takes 50 days for the patch to cover the entire lake , how many days would it take the patch to cover half of the lake ? 
Options: a ) 36 , b ) 2 ^ 4 * 3 , c ) 24 , d ) 49 , e ) 47

Answer:
d