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 cars , car 1 and car 2 move towards each other from e and y respectively with respective speeds of 20 m / s and 15 m / s . after meeting each other car 1 reaches y in 10 seconds . in how many seconds does car 2 reach e starting from y ? 
Options: a ) 15.5 sec , b ) 8.4 sec , c ) 33.6 sec , d ) 31.11 sec , e ) 16.8 sec

A: d
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Q: Problem: in what time will a train 20 m long cross an electric pole , it its speed be 144 km / hr ? 
Options: a ) 2.5 sec , b ) 2.8 sec , c ) 0.5 sec , d ) 2.3 sec , e ) 1.5 sec

A: c
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Q: Problem: a small water pump would take 3 hours to fill an empty tank . a larger pump would take 1 / 4 hour to fill the same tank . how many hours would it take both pumps , working at their respective constant rates , to fill the empty tank if they began pumping at the same time ? 
Options: a ) 3 / 13 , b ) 1 / 5 , c ) 1 / 10 , d ) 1 / 3 , e ) 1 / 7

A:
a
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