Earth's atmosphere is primarily composed of
a. argon
b. oxygen
c. nitrogen
d. carbon dioxide
the is between the troposphere and the mesosphere in earth's atmosphere.
a. exosphere
b. ionosphere
c. stratosphere
d. thermosphere

1.- C. Nitrogen

2.- C. Stratosphere

Explanation:  

1.- The atmosphere is mostly composed of Nitrogen, which occupies a total of 78%. It is followed by oxygen with 21%, argon with 0.9% and carbon dioxide with 0.03%.

The atmosphere is the part of the earth that contains gas and because of that it becomes the outermost layer with the least density.

The air currents that are in the atmosphere are responsible for regulating temperatures between day and night, to prevent them from being extreme, since they distribute the temperature along the earth's surface.

Nitrogen is very important since it is used by plants to generate amino acids and nutrients, which in turn are then ingested by animals.

2.- The stratosphere is located between the troposphere and the mesosphere, all within the atmosphere in the form of layers. The height at which this layer begins varies by location. In the polar regions it can go between 6 and 9 km and in the equatorial regions between 16 and 20.

Because this layer absorbs the ozone molecules, its temperature increases as it reaches more height. Being the minimum -55 ° and reaching 17 °.

In the lower areas the temperature is normal and stable and has very low humidity.