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: a tank can be filled by two pipes a and b in 60 minutes and 40 minutes respectively . how many minutes will it take to fill the tank from empty state if b is used for the first half time and then a and b fill it together for the other half . 
Options: a ) 15 mins , b ) 20 mins , c ) 25 mins , d ) 30 mins , e ) 35 mins

A: d
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Q: Problem: a man can do a piece of work in 6 days , but with the help of his son he can do it in 3 days . in what time can the son do it alone ? 
Options: a ) 7 days , b ) 6 days , c ) 5 days , d ) 4 days , e ) none of these

A:
b
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