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: two trains 180 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks . the time which they take to cross each other is ? 
Options: a ) 10.7 , b ) 10.9 , c ) 10.24 , d ) 12.24 , e ) 18.8
d

Problem: if a truck is traveling at a constant rate of 54 kilometers per hour , how many seconds will it take the truck to travel a distance of 600 meters ? ( 1 kilometer = 1000 meters ) 
Options: a ) 18 , b ) 24 , c ) 30 , d ) 36 , e ) 40
e

Problem: a circular rim 28 inches in diameter rotates the same number of inches per second as a circular rim 35 inches in diameter . if the smaller rim makes x revolutions per second , how many revolutions per second does the larger rim makes in terms of x ? 
Options: ['a ) 4 x / 5', 'b ) 75 x', 'c ) 48 x', 'd ) 24 x', 'e ) x / 75']

a