1. Which gas makes up approximately 21% of the atmopshere?
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2. Approximately what percentage of the air is carbon dioxide?
3. Which gas is present in the atmosphere in the greatest amount?
- carbon dioxide
4. What formed the early atmosphere?
- volatile compounds and elements released from molten rock.
5. Where did the oceans come from?
- As the atmosphere cooled below 100oC, steam condensed
- From plants
- From volcanoes