One Star in a Binary Will Almost Always Become a Red

question 21

Multiple Choice

One star in a binary will almost always become a red giant before the other because

• A) one star is always larger in radius than the other.
• B) binaries always have one star twice as massive as the other.
• C) small differences in main-sequence masses yield large differences in main-sequence lifetimes.
• D) the more massive binary star always gets more mass from the less massive binary star when both are main-sequence stars.
• E) one star always spins faster than the other.

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Definitions:

Contribution Margin Ratio

The contribution margin ratio calculates the proportion of sales revenue that exceeds variable costs, showing what portion of sales contributes to covering fixed costs and generating profit.

Selling Price

The amount at which a product or service is sold to customers, determined by factors such as market demand, production costs, and competition.

Variable Cost

Costs that vary directly with the level of production or business activity.

Sales Dollars

The revenue generated from goods or services sold, expressed in dollars.