Absorption Lines Due to Interstellar Gas

question 87

Multiple Choice

Absorption lines due to interstellar gas

• A) are wider than the lines from stars because the gas is hotter than most stars.
• B) are more narrow than the lines from stars because the gas has a lower pressure than stars.
• C) indicate that the interstellar medium contains dust.
• D) indicate that the interstellar medium is expanding away from the sun.
• E) none of the above.

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Definitions:

Marginal Cost

The expense associated with manufacturing an extra unit of a product.

Average Total Cost

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

Total Variable Cost

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

Average Variable Cost

The variable cost per unit of output, calculated by dividing total variable costs by the quantity of output produced.