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'.

Input: Consider Input: Problem: there are two tanks a & b with same capacity of 20 litres . if the water inflow rate ( speed ) in tank a is 2 litres per hour & in tank b is 4 litres per hour . how much longer tank a takes to fill than tank b ? 
Options: a ) 4 hours , b ) 5 hours , c ) 3 hours , d ) 2 hours , e ) 1 hour

Output: b


Input: Consider Input: Problem: a train 140 meters long takes 6 seconds to cross a man walking at 5 kmph in the direction opposite to that of the train . find the speed of the train . 
Options: a ) 45 kmph , b ) 50 kmph , c ) 55 kmph , d ) 60 kmph , e ) 79 kmph

Output: e


Input: Consider Input: Problem: tim and é lan are 180 miles away from one another . they are starting to move towards each other simultaneously , tim at a speed of 10 mph and é lan at a speed of 5 mph . if every hour they double their speeds , what is the distance that tim will pass until he meets é lan ? 
Options: a ) 130 miles . , b ) 135 miles . , c ) 145 miles . , d ) 120 miles . , e ) 165 miles .


Output: d