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'.

Problem: a can do a piece of work in 4 hours ; b and c together can do it in 3 hours , which a and c together can do it in 2 hours . how long will b alone take to do it ? 
Options: a ) 15 hours , b ) 14 hours , c ) 12 hours , d ) 74 hours , e ) 79 hours
c

Problem: if the wheel is 14 cm then the number of revolutions to cover a distance of 968 cm is ? 
Options: a ) a ) 15 , b ) b ) 10 , c ) c ) 14 , d ) d ) 12 , e ) e ) 11
e

Problem: a work which could be finished in 12 days was finished 3 days earlier after 10 more men joined . the number of men employed was ? 
Options: a ) 22 , b ) 20 , c ) 88 , d ) 71 , e ) 10

e