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: the speed at which a man can row a boat in still water is 16 kmph . if he rows downstream , where the speed of current is 4 kmph , what time will he take to cover 100 metres ? 
Options: a ) 23 , b ) 27 , c ) 28 , d ) 12 , e ) 18

A: e
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Q: Problem: how many seconds will a train 100 meters long take to cross a bridge 160 meters long if the speed of the train is 36 kmph ? 
Options: a ) 26 , b ) 72 , c ) 25 , d ) 82 , e ) 27

A: a
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Q: Problem: the length of a room is 7 m and width is 4.75 m . what is the cost of paying the floor by slabs at the rate of rs . 900 per sq . metre . 
Options: a ) 25650 , b ) 25750 , c ) 26550 , d ) 26750 , e ) 29925

A:
e
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