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'.
--------
Question: 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

Answer: d


Question: Problem: a boat can travel with a speed of 16 km / hr in still water . if the rate of stream is 5 km / hr , then find the time taken by the boat to cover distance of 84 km downstream . 
Options: a ) 4 hours , b ) 5 hours , c ) 6 hours , d ) 7 hours , e ) 8 hours

Answer: a


Question: Problem: if two trains are 120 miles apart and are traveling toward each other at constant rate of 30 miles per hour and 40 miles per hour , respectively , how far apart will they be 1 hour before they meet ? 
Options: a ) 10 , b ) 30 , c ) 40 , d ) 50 , e ) 70

Answer:
e