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: if an object travels at eight feet per second , how many feet does it travel in one hour ? 
Options: a ) 34880 , b ) 3778 , c ) 12788 , d ) 18000 , e ) 28800

A: e
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Q: Problem: two trains of length 150 m and 280 m are running towards each other on parallel lines at 42 kmph and 30 kmph respectively . in what time will they be clear of each other from the moment they meet ? 
Options: a ) 22 sec , b ) 77 sec , c ) 76 sec , d ) 21.5 sec , e ) 66 sec

A:
d
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