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: two trains a and b starting from two points and travelling in opposite directions , reach their destinations 9 hours and 4 hours respectively after meeting each other . if the train a travels at 100 kmph , find the rate at which the train b runs . 
Options: a ) 40 , b ) 60 , c ) 150 , d ) 80 , e ) 100

Answer: c


Question: Problem: two pipes a and b can separately fill a cistern in 24 minutes and 48 minutes respectively . there is a third pipe in the bottom of the cistern to empty it . if all the three pipes are simultaneously opened , then the cistern is full in 12 minutes . in how much time , the third pipe alone can empty the cistern ? 
Options: a ) 90 min , b ) 48 min , c ) 54 min , d ) 120 min , e ) 130 min

Answer: b


Question: Problem: if john covers a certain distance in 1 hr . 24 min . by covering two third of the distance at 4 kmph and the rest at 5 kmph , then find the total distance 
Options: a ) 4 km , b ) 6 km , c ) 6.8 km , d ) 7.2 km , e ) none of these

Answer:
b