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: 45 men working 8 hours per day dig 40 m deep . how many extra men should be put to dig to a depth of 50 m working 6 hours per day ? 
Options: a ) 10 , b ) 20 , c ) 30 , d ) 40 , e ) 50

Answer: c


Question: Problem: in a 500 m race , the ratio of the speeds of two contestants a and b is 3 : 4 . a has a start of 155 m . then , a wins by : 
Options: a ) 60 m , b ) 20 m , c ) 40 m , d ) 20 m , e ) 23 m

Answer: c


Question: Problem: a car traveled 560 miles per tankful of gasoline on the highway and 336 miles per tankful of gasoline in the city . if the car traveled 6 fewer miles per gallon in the city than on the highway , how many miles per gallon did the car travel in the city ? 
Options: a ) 9 , b ) 16 , c ) 21 , d ) 22 , e ) 27

Answer:
a