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: 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

A: d
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Q: Problem: a train running at a speed of 60 kmph crosses a pole in 18 seconds . what is the length of the train ? 
Options: a ) 120 m , b ) 300 m , c ) 190 m , d ) 150 m , e ) 160 m

A: b
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Q: Problem: if an object travels at ten feet per second , how many feet does it travel in one hour ? 
Options: a ) 34880 , b ) 37780 , c ) 36000 , d ) 18000 , e ) 28810

A:
c
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