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: if 14 men do a work in 80 days , in how many days will 20 men do it ? 
Options: a ) 18 days , b ) 38 days , c ) 42 days , d ) 48 days , e ) 56 days

A: e
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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: the length of the bridge , which a train 145 metres long and travelling at 45 km / hr can cross in 30 seconds , is ? 
Options: a ) 76 m , b ) 178 m , c ) 230 m , d ) 187 m , e ) 176 m

A:
c
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