Which Is a Plausible Explanation for the Presence of Carbon

question 111

Multiple Choice

Which is a plausible explanation for the presence of carbon dioxide in Earth's early atmosphere?

• A) Volcanic eruptions could have released carbon dioxide into the atmosphere.
• B) Cyanobacteria were present on Earth 3.5 billion years ago.
• C) Retroviruses could have catalyzed the formation of carbon dioxide.
• D) Geysers may have produced Earth's early environment.
• E) Chemical reactions with water would have resulted in the formation of carbon dioxide.

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Definitions:

Opportunity Cost

The loss of potential gain from other alternatives when one alternative is chosen.

Economic Profit

The difference between a firm's total revenues and its total costs, including both explicit and implicit costs.

Economic Profit

The difference between total revenue and total cost, including both explicit and implicit costs.

Accounting Profit

The difference between a company's total revenue and its explicit costs.