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'.
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Question: Problem: noelle walks from point a to point b at an average speed of 6 kilometers per hour . at what speed , in kilometers per hour , must noelle walk from point b to point a so that her average speed for the entire trip is 7 kilometers per hour ?
Options: a ) 6.75 , b ) 7 , c ) 7.25 , d ) 7.5 , e ) 8.4

Answer: e

Question: Problem: a flagpole 18 meters high casts a shadow of length 45 meters . if a building under similar conditions casts a shadow of length 55 meters , what is the height of the building ( in meters ) ?
Options: a ) 20 , b ) 22 , c ) 24 , d ) 26 , e ) 28

Answer: b

Question: Problem: 30 men can do a work in 40 days . when should 16 men leave the work so that the entire work is completed in 40 days after they leave the work ?
Options: a ) 87 days , b ) 14 days , c ) 55 days , d ) 44 days , e ) 22 days

Answer:
b