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 , b and c can complete a piece of work in 24 , 6 and 12 days respectively . working together , they will complete the same work in : 
Options: a ) 33 / 7 , b ) 43 / 7 , c ) 24 / 7 , d ) 19 / 7 , e ) none
[A]: c


[Q]: Problem: pipes a and b can fill a tank in 3 and 4 hours . pipe c can empty it in 4 hours . if all pipes are opened together , then the tank will be filled in ? 
Options: a ) 3 hr , b ) 1 / 2 hr , c ) 1 hr , d ) 9 / 7 hr , e ) 5 / 3 hr
[A]: a


[Q]: Problem: x is able to do a piece of work in 14 days and y can do the same work in 20 days . if they can work together for 5 days , what is the fraction of work completed ? 
Options: a ) 15 / 28 , b ) 17 / 28 , c ) 13 / 28 , d ) 19 / 28 , e ) 11 / 28
[A]:
b