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 can do a piece of work in 80 days and b in 100 days . they work together for 20 days and then b goes away . in how many days will a finish the remaining work ? 
Options: a ) 33 days , b ) 44 days , c ) 55 days , d ) 42 days , e ) 32 days

Answer: b


Question: Problem: a man can row upstream at 5 kmph and downstream at 25 kmph , and then find the speed of the man in still water ? 
Options: a ) 15 , b ) 77 , c ) 30 , d ) 88 , e ) 34

Answer: a


Question: Problem: a and b can do a piece of work in 7 days . with the help of c they finish the work in 4 days . c alone can do that piece of work in ? 
Options: a ) 33 , b ) 9 1 / 3 , c ) 30 , d ) 88 , e ) 11

Answer:
b