No one answers my Questions :( Please help its my last one:

Name three sources of atmospheric carbon dioxide. (Write in complete sentences and be very detailed.)
This is science.
First and best answer gets 5 stars, a thanks, and a brainliest!

Doing this because I know I'm kickass at Chemistry.

One source would be human emissions. As humans, we use a lot of machines (like power plants) that produce large amounts of carbon dioxide into the atmosphere. The ocean also produces a lot of carbon dioxide via the evaporation cycle. Polluted waters eventually will go into the atmosphere. Volcanoes, even when not erupted, emit a lot of carbon dioxide as well. Dormant underground magma releases carbon dioxide through the Earth's pores, and even when a volcano erupts, it produces carbon dioxide as well.

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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