The Number of Confirmed Extrasolar Planets

question 116

Multiple Choice

The number of confirmed extrasolar planets

• A) was about 800 at the time of publication but is rising rapidly due to new observations by the Kepler spacecraft.
• B) is about 600, and is not expected to rise very much.
• C) is about 800, and is rising slowly, as observations are quite difficult.
• D) has been decreasing as some observations thought to be planets have been disproven.
• E) is zero; there are observations thought to be of extrasolar planets but none has yet been confirmed.

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Definitions:

Marginal Revenue

The additional income received from selling one more unit of a good or service, used to analyze and optimize profit and pricing strategies.

Economic Profits

Profits exceeding the total costs of resources used, including both explicit and implicit costs.

Opportunity Costs

The financial loss associated with overlooking the alternative that is considered second-best when making a choice.

Average Total Cost

The total cost of production (fixed and variable costs combined) divided by the total quantity of output produced.