Which of the Following Provides Evidence That Our 24-Hour Sleep-Waking

question 85

Multiple Choice

Which of the following provides evidence that our 24-hour sleep-waking cycle is the result of a built-in mechanism?

• A) some people sleep only 5-6 hours a night; others sleep 7-8 hours.
• B) only a little more sleep is needed after an active day than after a busy day.
• C) people who live in a near-polar region still generate close to a 24-hour cycle of sleeping and being awake.
• D) people who are forced to stay awake for long periods of time develop severe health problems.

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Definitions:

Negative Economic Profit

A situation where a firm's total revenue is less than its total costs, including opportunity costs.

Market Price

The current value at which an asset or service can be bought or sold in a competitive marketplace.

Zero Economic Profit

A situation where a firm's total revenue is exactly equal to its total costs, including opportunity costs.

Economic Profits

The excess of total revenues over total costs, including both explicit and implicit costs.