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'.

Ex Input:
Problem: a man ' s regular pay is $ 3 per hour up to 40 hours . overtime is twice the payment for regular time . if he was paid $ 180 , how many hours overtime did he work ?
Options: a ) 8 , b ) 5 , c ) 9 , d ) 6 , e ) 10

Ex Output:
e

Ex Input:
Problem: a train running at the speed of 54 km / hr crosses a pole in 7 seconds . find the length of the train .
Options: a ) 150 meter , b ) 105 meter , c ) 140 meter , d ) 135 meter , e ) none of these

Ex Output:
b

Ex Input:
Problem: a constructor estimates that 8 people can paint mr khans house in 3 days . if he uses 4 people instead of 8 , how long will they take to complete the job ?
Options: a ) 6 , b ) 8 , c ) 3 , d ) 4 , e ) 0

Ex Output:
a