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 together can do a work in 4 days . if a alone can do it in 20 days . in how many days can b alone do it ? 
Options: a ) 11 , b ) 5 , c ) 6 , d ) 8 , e ) 25

Answer: b


Question: Problem: a water tank is four - fifths full . pipe a can fill a tank in 10 minutes and pipe b can empty it in 6 minutes . if both the pipes are open , how many minutes will it take to empty or fill the tank completely ? 
Options: a ) 6 , b ) 9 , c ) 10 , d ) 12 , e ) 15

Answer: d


Question: Problem: the current in a river is 8 mph . a boat can travel 20 mph in still water . how far up the river can the boat travel if the round trip is to take 10 hours ? 
Options: a ) 69 miles , b ) 84 miles , c ) 96 miles , d ) 100 miles , e ) 112 miles

Answer:
b