The Measurement of Cosmic Distances Was Helped Tremendously by the Discovery

question 26

Multiple Choice

The measurement of cosmic distances was helped tremendously by the discovery, in the early part of the 20th century, that in Cepheid variable stars, the average luminosity was related to:

• A) their radial velocity
• B) the abundance of hydrogen in their atmospheres
• C) their distance from the Sun
• D) the length of time they took to vary
• E) their parallax

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Definitions:

Market Price

The prevailing cost at which one can buy or sell an asset or service.

Marginal Cost

The augmentation in total costs associated with the production of an additional unit of a product or service.

Cartel

A group of independent market participants who collude to control prices and production in order to monopolize a market.

Fixed Cost

Costs that do not change with the level of output, such as rent or salaries.