An Astronomer Is Interested in a Galaxy Called M31, the Nearest

question 11

Multiple Choice

An astronomer is interested in a galaxy called M31, the nearest galaxy that resembles our Milky Way. It is about 2 million lightyears away. Which technique would be able to give us a distance to this galaxy?

• A) parallax
• B) radar reflections
• C) period-luminosity relation for Cepheid variables
• D) Kepler's laws
• E) you can't fool me: there is no way at present to get a distance to an object so far away

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Definitions:

Marginal Revenue

The surplus earnings acquired through the sale of an extra product or service unit.

Increasing Output

The process of raising the quantity of goods or services produced by a company or economy, often aiming for higher efficiency and profitability.

Marginal Analysis

The examination of the additional benefits of an activity compared to the additional costs incurred by that same activity.

Total Cost

The sum of all expenses incurred in the production of goods or services, including both fixed and variable costs.