TASK DEFINITION: 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: Problem: a man sitting in a train which is travelling at 64 kmph observes that a goods train travelling in a opposite direction , takes 18 seconds to pass him . if the goods train is 420 m long , find its speed . 
Options: a ) 32 , b ) 15 , c ) 18 , d ) 20 , e ) 25

SOLUTION: d

PROBLEM: Problem: if 36 men can do a piece of work in 5 hours , in how many hours will 15 men do it ? 
Options: a ) 12 , b ) 38 , c ) 60 , d ) 88 , e ) 72

SOLUTION: a

PROBLEM: Problem: pipe p can fill a tank in 3 hours , pipe q in 9 hours and pipe r in 18 hours . if all the pipes are open , in how many hours will the tank be filled ? 
Options: a ) 2 hours , b ) 2.4 hours , c ) 3 hours , d ) 3.5 hours , e ) 4.5 hours

SOLUTION:
a