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'.

[Q]: Problem: mariah has decided to hire three workers . to determine whom she will hire , she has selected a group of 12 candidates . she plans to have one working interview with 3 of the 12 candidates every day to see how well they work together . how many days will it take her to have working interviews with all the different combinations of job candidates ? 
Options: a ) 720 , b ) 120 , c ) 300 , d ) 30 , e ) 333
[A]: c


[Q]: Problem: a is twice as good a workman as b and together they complete a work in 12 days . in how many days a alone can do the work ? 
Options: a ) 32 , b ) 33 , c ) 34 , d ) 35 , e ) 36
[A]: e


[Q]: Problem: i flew my tiny seaplane to visit my mother . on the flight up , i flew at 140 mph . on the way home , i flew 88 mph . what was my average speed for the trip ? 
Options: a ) 114 mph , b ) 110 mph , c ) 88 mph , d ) 100 mph , e ) 99 mph
[A]:
a