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: the pilot of a small aircraft with a 40 - gallon fuel tank wants to fly to cleveland , which is 480 miles away . the pilot recognizes that the current engine , which can fly only 8 miles per gallon , will not get him there . by how many miles per gallon must the aircraft ’ s fuel efficiency be improved to make the flight to cleveland possible ? 
Options: a ) 2 , b ) 4 , c ) 12 , d ) 40 , e ) 160

Ex Output:
b


Ex Input:
Problem: tom traveled the entire 60 miles trip . if he did the first 15 miles of at a constant rate 24 miles per hour and the remaining trip of at a constant rate 45 miles per hour , what is the his average speed , in miles per hour ? 
Options: a ) 35.62 mph , b ) 25.45 mph , c ) 34.52 mph , d ) 36.92 mph , e ) 36.29 mph

Ex Output:
d


Ex Input:
Problem: a rotameter is a device that measures flow of liquid and gases . when measuring liquid phase flows , 2.5 inches represent 60 liters per minute of liquid . with gas measurements the rotameter moves 50 % of the movement he moves with the liquid phase . how many liters of gas passed through the rotameter if it measured 4 inches ? 
Options: a ) 176 , b ) 192 , c ) 202 , d ) 218 , e ) 284

Ex Output:

b