Why Should Galaxy Collisions Have Been More Common in the Past

question 4

Multiple Choice

Why should galaxy collisions have been more common in the past than they are today?

• A)Galaxies were more active in the past and therefore would have collided with each other more frequently.
• B)Galaxies were much bigger in the past since they had not contracted completely.
• C)Galaxies were closer together in the past because the universe was smaller.
• D)Galaxies attracted each other more strongly in the past because they were more massive;they had not yet turned most of their mass into stars and light.
• E)Galaxy collisions shouldn't have been more common in the past than they are now.

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Definitions:

Marginal Costs

The supplementary expense incurred from making one more unit of a product or service.

Fixed Costs

Costs that do not vary with the level of output in the short term, such as rent, salaries, and loan payments.

Total Revenue

The total amount of money received by a firm from the sale of its goods or services, calculated as price times quantity sold.

Total Variable Cost

The total of all costs that vary with the level of production, such as materials and labor costs.