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'.

[EX Q]: Problem: a and b together can do a work in 4 days . if a alone can do it in 20 days . in how many days can b alone do it ? 
Options: a ) 11 , b ) 5 , c ) 6 , d ) 8 , e ) 25
[EX A]: b

[EX Q]: Problem: if an object travels at eight feet per second , how many feet does it travel in one hour ? 
Options: a ) 34880 , b ) 3778 , c ) 12788 , d ) 18000 , e ) 28800
[EX A]: e

[EX Q]: Problem: car a runs at the speed of 65 km / hr & reaches its destination in 8 hr . car b runs at the speed of 75 km / h & reaches its destination in 4 h . what is the respective ratio of distances covered by car a & car b ? 
Options: a ) 26 : 15 , b ) 12 : 7 , c ) 13 : 7 , d ) 15 : 6 , e ) 13 : 6
[EX A]:
a