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: two trains are running in opposite directions in the same speed . the length of each train is 120 meter . if they cross each other in 12 seconds , the speed of each train ( in km / hr ) is 
Options: a ) 30 km / hr , b ) 36 km / hr , c ) 80 km / hr , d ) 90 km / hr , e ) none of these

A: b
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Q: Problem: if the wheel is 14 cm then the number of revolutions to cover a distance of 3520 cm is ? 
Options: a ) 22 , b ) 28 , c ) 17 , d ) 12 , e ) 40

A: e
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Q: Problem: a and b can finish a work in 16 days while a alone can do the same work in 20 days . in how many days b alone will complete the work ? 
Options: a ) 76 days , b ) 48 days , c ) 80 days , d ) 31 days , e ) 22 days

A:
c
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