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 car drives 90 miles on local roads at 30 mph , and 75 miles on the highway at 60 mph , what is the average speed of the entire trip ? 
Options: a ) 36 mph , b ) 40 mph , c ) 39 mph , d ) 42 mph , e ) 38 mph
[EX A]: c

[EX Q]: Problem: 45 men took a dip in a water tank 40 m long and 20 m broad on a religious day . if the average displacement of water by a man is 4 m 3 , then the rise in the water level in the tank will be : 
Options: a ) 20 cm , b ) 25 cm , c ) 35 cm , d ) 50 cm , e ) none of these
[EX A]: e

[EX Q]: Problem: a can do a piece of work in 4 hours . a and c together can do it in just 2 hours , while b and c together need 3 hours to finish the same work . in how many hours b can complete the work ? 
Options: a ) 10 hours , b ) 12 hours , c ) 16 hours , d ) 18 hours , e ) 20 hours
[EX A]:
b