Hello there!
I hope you and your family are staying safe and healthy during this unprecendented time.
A) What is the work done?
Answer: We need to use the formula



B) What is the work done on the cart by the gravitational force?
Alright, we know that the gravitional force is perpendicular to the diplacement. Therefore, we gonna use the following formula:


C) What is the work done on the cart by the shopper?
This is the easier part, since we already know that the work done by the shopper is the same as the work done by the friction force

D) Find the force the shopper exerts, using energy considerations.

E) What is the total work done?
You just need to add them:

Some properties I know are
melting point<span>
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boiling point<span>
, and index of </span>
refraction<span>.</span>
<span>the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth.
Hope this helps.
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Answer: The correct answer is B. "the electromagnetic waves appear more red in color".
Explanation:
Scientists use the Doppler effect to understand the universe by determining the motion of the object.
Red shift: The apparent frequency of light decreases as the source object in space moves away from us. The light is shifted to red end. The apparent frequency decreases and there is increase in the wavelength of the light.
Blue shift: The apparent frequency of light increases as the object in space moves towards us. The light is shifted to blue end. In this case, there is decrease in the wavelength of the light. The frequency of the wave increases.
In the given problem, when the light source moves further away from an observer, the electromagnetic waves appear red in color.
Therefore, the correct option is (B).