What Happens to Cores of Main-Sequence Stars as They Age

question 16

Multiple Choice

What happens to cores of main-sequence stars as they age?

• A) They cool down because they run out of hydrogen fuel.
• B) They cool down because they expand.
• C) They heat up because they contract.
• D) They heat up because helium is more tightly bound than hydrogen.

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Definitions:

Confidence Interval

A series of values, taken from sampled data, believed to cover the value of a hidden population parameter.

Defective Fuses

Products in a batch of fuses that do not meet the required quality or performance standards.

Normal Distribution

A continuous probability distribution characterized by a symmetric bell-shaped curve, representing random variables with mean and variance.

Test Statistic

A numerical value calculated from a sample that is used in statistical hypothesis testing to determine whether to reject the null hypothesis.