Which of the Following Is True

question 119

Multiple Choice

Which of the following is true?

• A)Monopolists, monopolistically competitive firms and perfectly competitive firms all earn positive economic profits in the long run.
• B)Monopolists, monopolistically competitive firms and perfectly competitive firms all earn zero economic profits in the long run.
• C)Only monopolists and monopolistically competitive firms, but not perfectly competitive firms, can earn positive economic profits in the long run.
• D)Monopolists, monopolistically competitive firms and perfectly competitive firms can potentially all earn positive economic profits in the short run.
• E)Only monopolists and monopolistically competitive firms, but not perfectly competitive firms, can earn positive economic profits in the short run.

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Definitions:

Nonequivalent Control

A research design where the control group is not randomly assigned, making it different in certain ways from the experimental group, which can affect the interpretation of results.

Control Time Series

A method in statistics and research that involves collecting data points from a single group or subject over a period of time to identify trends or effects of interventions.

External Validity

The degree to which a study's findings can be applied to different situations and various individuals.

Extraneous Variables

Variables that can influence the outcome of an experiment but are not the variables being studied.