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'.

Q: Problem: 9 . on level farmland , two runners leave at the same time from the intersection of two country roads . one runner jogs due north at a constant rate of 8 miles per hour while the second runner jogs due east at a constant rate that is 8 miles per hour faster than the first runner ' s rate . how far apart , to the nearest mile , will they be after 1 / 2 hour ? 
Options: a ) 6 , b ) 7 , c ) 8 , d ) 12 , e ) 9

A: e
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Q: Problem: rahul travels from a to b a distance of 200 miles in 5 hours . he returns to a in 4 hours . find his average speed ? 
Options: a ) 52.2 mph , b ) 61.9 mph , c ) 44.4 mph , d ) 35.7 mph , e ) 65.6 mph

A: c
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Q: Problem: a person can swim in still water at 10 km / h . if the speed of water 4 km / h , how many hours will the man take to swim back against the current for 12 km ? 
Options: a ) 2 , b ) 7 , c ) 5 , d ) 9 , e ) 6

A:
a
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