What Is the Status of Our Search for Life Elsewhere

question 23

Multiple Choice

What is the status of our search for life elsewhere in the universe?

• A) Life has been discovered elsewhere in the solar system.
• B) Signs of life have been discovered on Earth-like planets circling other stars elsewhere in the Milky Way Galaxy.
• C) Earthlike planets, with an abundance of liquid water, have been discovered around other stars, but signs of life have not yet been found on them.
• D) No exoplanets in habitable zones have yet been discovered.

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Definitions:

ATC

Average Total Cost, the per unit cost of production that includes all fixed and variable costs.

MR

Marginal Revenue, the additional income earned from selling one more unit of a good or service.

Economic Profit

The excess of total revenue over the complete aggregation of both transparent and hidden costs.

Marginal Revenue

The supplementary income a company accrues from the sale of one additional unit of a product or service.