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 , b , k start from the same place and travel in the same direction at speeds of 30 km / hr , 40 km / hr , 80 km / hr respectively . b starts two hours after a . if b and k overtake a at the same instant , how many hours after a did k start ? 
Options: a ) 2 , b ) 3 , c ) 4 , d ) 5 , e ) 6
[EX A]: d

[EX Q]: Problem: a train is 360 meter long is running at a speed of 90 km / hour . in what time will it pass a bridge of 140 meter length ? 
Options: a ) 27 seconds , b ) 29 seconds , c ) 40 seconds , d ) 11 seconds , e ) 20 seconds
[EX A]: e

[EX Q]: Problem: walking with 3 / 5 of my usual speed , i miss the bus by 5 minutes . what is my usual time ? 
Options: a ) 16 min , b ) 26 min , c ) 34 min , d ) 20 min , e ) 15 min
[EX A]:
e