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: 63 men working 8 hours per day dig 30 m deep . how many extra men should be put to dig to a depth of 50 m working 6 hours per day ? 
Options: a ) a ) 87 , b ) b ) 77 , c ) c ) 66 , d ) d ) 55 , e ) e ) 97
[A]: b


[Q]: Problem: 8 persons can build a wall 140 m long in 42 days . in how many days can 30 persons complete a similar wall 100 m long ? 
Options: a ) 12 , b ) 10 , c ) 8 , d ) 6 , e ) 5
[A]: c


[Q]: Problem: 69 persons can repair a road in 12 days , working 5 hours a day . in how many days will 30 persons , working 6 hours a day , complete the work ? 
Options: a ) 20 , b ) 23 , c ) 24 , d ) 25 , e ) 26
[A]:
b