Which Life Form Has Been Present on Earth the Longest

question 4

Multiple Choice

Which life form has been present on Earth the longest?

• A)jawed vertebrates
• B)humans
• C)microbes such as bacteria
• D)single-celled eukaryotes such as protists

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Definitions:

Fixed Cost

Costs that do not vary with the volume of production or sales, such as rent, salaries, and insurance premiums.

Variable Cost

Costs that change in proportion to the level of production or business activity.

Fixed Cost

Costs that do not change with the level of production or business activity, such as rent, salaries, and insurance.

Present Value

The current worth of a future sum of money or stream of cash flows given a specified rate of return.