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 train 1500 m long can cross an electric pole in 50 sec and then find the speed of the train ? 
Options: a ) 106 , b ) 107 , c ) 108 , d ) 109 , e ) 110

A: c
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Q: Problem: the sector of a circle has radius of 21 cm and central angle 180 o . find its perimeter ? 
Options: a ) 91.5 , b ) 92 , c ) 108 , d ) 94 , e ) 95

A: c
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Q: Problem: a cistern can be filled by a tap in 3 hours while it can be emptied by another tap in 9 hours . if both the taps are opened simultaneously , then after how much time will the cistern get filled ? 
Options: a ) 4.5 hrs , b ) 5 hrs , c ) 6.5 hrs , d ) 7.2 hrs , e ) 9.2 hrs

A:
a
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