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 42 men do a work in 25 days , in how many days will 50 men do it ? 
Options: a ) 23 , b ) 22 , c ) 19 , d ) 20 , e ) 21

A: e
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Q: Problem: convert the 15 / 36 m / s into kilometers per hour ? 
Options: a ) 1.7 , b ) 1.5 , c ) 1.3 , d ) 1.1 , e ) 1.2

A: b
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Q: Problem: two trains of length 120 m and 210 m are 80 m apart . they start moving towards each other on parallel tracks , at speeds 69 kmph and 82 kmph . after how much time will the trains meet ? 
Options: a ) 15 / 10 , b ) 19 / 10 , c ) 20 / 19 , d ) 16 / 10 , e ) 27 / 10

A:
b
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