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 and b can do a piece of work in 3 days , b and c in 4 days , c and a in 6 days . how long will c take to do it ? 
Options: a ) 33 , b ) 77 , c ) 24 , d ) 55 , e ) 71

Answer: c


Question: Problem: on a trip covering 400 km , a bicyclist travels the first 100 km at 20 km per hour and the remainder of the distance at 15 km per hour . what is the average speed , in km per hour , for the entire trip ? 
Options: a ) 15.5 , b ) 16.0 , c ) 16.5 , d ) 17.0 , e ) 17.5

Answer: b


Question: Problem: if 30 men take 15 days to to complete a job , in how many days can 25 men finish that work ? 
Options: a ) 18 , b ) 17 , c ) 16 , d ) 15 , e ) 14

Answer:
a