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: a courtyard is 25 meter long and 16 meter board is to be paved with bricks of dimensions 20 cm by 10 cm . the total number of bricks required is 
Options: a ) 16000 , b ) 18000 , c ) 20000 , d ) 22000 , e ) 24000
Example Output: c

Example Input: Problem: a , b and c can do a piece of work in 9 days , 14 days and 28 days respectively . how long will they taken , if all the three work together ? 
Options: a ) 4.12 days , b ) 4.52 days , c ) 3.52 days , d ) 2.52 days , e ) 4.92 days
Example Output: b

Example Input: Problem: jane makes toy bears . when she works with an assistant , she makes 89 percent more bears per week and works 10 percent fewer hours each week . having an assistant increases jane ’ s output of toy bears per hour by what percent ? 
Options: a ) 20 % , b ) 80 % , c ) 110 % , d ) 180 % , e ) 200 %
Example Output:
c