<span>Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of height. ... The term also applies to the refraction of sound.</span>
It should be A sorry if I’m wrong
Answer:
The average power the student expended to overcome gravity is 560W, Watts is a units of work it is Joules /time or kg*
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Explanation:
Weight = 700N

The power is the work in (Joules) or (N*m) in a determinate time (s) to get Watts (W) units for work

Using the formula t=root of 2h/g then where h=28 and g=9.8 then substitute so the answer is 2.4seconds