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: a train 140 m long is running with a speed of 50 km / hr . in what time will it pass a man who is running at 4 km / hr in the direction opposite to that in which the train is going ? 
Options: a ) 8.1 , b ) 7.0 , c ) 9.33 , d ) 8 , e ) 9

Output: c


Input: Consider Input: Problem: a water tank is four - fifths full . pipe a can fill a tank in 10 minutes and pipe b can empty it in 6 minutes . if both the pipes are open , how many minutes will it take to empty or fill the tank completely ? 
Options: a ) 6 , b ) 9 , c ) 10 , d ) 12 , e ) 15

Output: d


Input: Consider Input: Problem: a 180 m long train is running at 72 kmph . if it crossed the platform in 20 sec . then find the platform length ? 
Options: a ) 220 m , b ) 110 m , c ) 230 m , d ) 100 m , e ) 90 m


Output: a