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 car traveling at a certain constant speed takes 10 seconds longer to travel 1 km than it would take to travel 1 km at 80 km / hour . at what speed , in km / hr , is the car traveling ? 
Options: a ) 70 , b ) 72 , c ) 74 , d ) 65 , e ) 78
d

Problem: an automotive test consisted of driving a car the same distance 3 separate times , first at an average rate of 4 miles per hour , then 5 miles per hour , then 6 miles per hour . if the test took 37 hours to complete , how many miles was the car driven during the entire test ? 
Options: a ) 100 , b ) 120 , c ) 180 , d ) 200 , e ) 240
c

Problem: the h . c . f . of two numbers is 12 and their l . c . m . is 600 . if one of the number is 45 , find the other ? 
Options: a ) 100 , b ) 160 , c ) 120 , d ) 200 , e ) 150

b