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 tree is 12 m tall and casts an an 8 m long shadow . at the same time , a flag pole caste a 100 m long shadow . how long is the flag pole ? 
Options: a ) 150 m , b ) 200 m , c ) 125 m , d ) 115 m , e ) none

Ex Output:
a


Ex Input:
Problem: stacy has a 81 page history paper due in 3 days . how many pages per day would she have to write to finish on time ? 
Options: a ) 9 , b ) 27 , c ) 10 , d ) 8.5 , e ) 6

Ex Output:
b


Ex Input:
Problem: how many seconds will a train 140 meters long take to cross a bridge 150 meters long if the speed of the train is 36 kmph ? 
Options: a ) 28 sec , b ) 29 sec , c ) 24 sec , d ) 25 sec , e ) 26 sec

Ex Output:

b