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: two taps a and b can fill a cistern in 12 minutes and 18 minutes respectively . they are turned on at the same time . if the tap a is turned off after 4 minutes , how long will tap b take to fill the rest of the cistern ? 
Options: a ) 8 min . , b ) 9 min . , c ) 10 min . , d ) 7 min . , e ) none of these

Ex Output:
a


Ex Input:
Problem: a and b complete a work in 4 days . a alone can do it in 6 days . if both together can do the work in how many days ? 
Options: a ) 3.75 days , b ) 3.7 days , c ) 3.6 days , d ) 2.4 days , e ) 5.75 days

Ex Output:
d


Ex Input:
Problem: water boils at 212 ° f or 100 ° c and melts at 32 ° f or 0 ° c . if the temperature of the particular day is 35 ° c , it is equal to 
Options: a ) 50 ° f , b ) 76 ° f , c ) 95 ° f , d ) 110 ° f , e ) 120 ° f

Ex Output:

c