Before Copernicus challenged the ideas of Ptolomy people accepted the belief that . a.
planets revolved around the sun
c.
planets revolved around the earth
b.
planets revolved around the moon
d.
planets did not move at all

C.  planets revolved around the earth

Explanation:

The other planets besides the sun revolve around the earth says scientists that are in the ISS --International Space Station-- watching it all happen.

This answer was gotten by watching a CNN 10 Teens video.

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the correct answer is ) possibility.

demonstrating opportunity cost is done through production possibility.

the opportunity cost can be demonstrated using the production possibility frontier or curve. this graphic shows the total number of possibilities for two products when we have the resources needed and used in an efficient manner. the main resources could be money, labor, and technology. the curve shows that the production of one good increases when the production of the othe