Answer:
A: 0 to 4 percent
recipitation
Explanation:
Because the gases like carbon dioxide, nitrous oxides, methane, and ozone are trace gases that account for about a tenth of one percent of the atmosphere. Water vapor is unique in that its concentration varies from 0-4% of the atmosphere depending on where you are and what time of the day it is.
Basically the Earth is layered because of gravity. The earth formed in the molten state. The liquid iron which is very dense fell to the center. The rest of the earth is made up of silicate materials with SiO2 being the main component.
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