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'.

Example Input: Problem: the speed of a car is 60 km in the first hour and 30 km in the second hour . what is the average speed of the car ? 
Options: a ) 45 kmph , b ) 65 kmph , c ) 75 kmph , d ) 85 kmph , e ) 90 kmph
Example Output: a

Example Input: Problem: in what time will a railway train 60 m long moving at the rate of 36 kmph pass a telegraph post on its way ? 
Options: a ) 2 , b ) 7 , c ) 8 , d ) 6 , e ) 9
Example Output: d

Example Input: Problem: find the angle between the hour hand and the minute hand of a clock when 3.25 . 
Options: a ) 47.5 , b ) 46.5 , c ) 45.5 , d ) 48.5 , e ) 44.5
Example Output:
a