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 upstream at 15 kmph and downstream at 25 kmph , and then find the speed of the man in still water ? 
Options: a ) 27 , b ) 29 , c ) 30 , d ) 20 , e ) 24

Answer: d


Question: Problem: the length of the bridge , which a train 140 metres long and travelling at 45 km / hr can cross in 30 seconds , is ? 
Options: a ) 255 , b ) 267 , c ) 235 , d ) 277 , e ) 211

Answer: c


Question: Problem: a man , a woman and a boy can together complete a piece of work in 3 days . if a man alone can do it in 6 days and a women alone in 18 days , how long will a boy take to complete the work ? 
Options: a ) 6 days , b ) 8 days , c ) 9 days , d ) 7 days , e ) 5 days

Answer:
c