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: a motorcyclist started riding at highway marker a , drove 120 miles to highway marker b , and then , without pausing , continued to highway marker c , where she stopped . the average speed of the motorcyclist , over the course of the entire trip , was 40 miles per hour . if the ride from marker a to marker b lasted 3 times as many hours as the rest of the ride , and the distance from marker b to marker c was half of the distance from marker a to marker b , what was the average speed , in miles per hour , of the motorcyclist while driving from marker b to marker c ? 
Options: a ) 40 , b ) 45 , c ) 50 , d ) 55 , e ) 67.5

A: e
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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
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Q: Problem: if 9 workers can build 9 cars in 9 days , then how many days would it take 7 workers to build 7 cars ? 
Options: a ) 6 , b ) 7 , c ) 8 , d ) 9 , e ) 10

A:
d
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