Why Does the Sun Brighten with Time

question 59

Multiple Choice

Why does the Sun brighten with time?

• A) as time progresses, helium starts to fuse in the core, in addition to hydrogen, leading to an increase in brightness
• B) as hydrogen is converted into helium in the core, the number of hydrogen nuclei decreases, decreasing the fusion rate. To maintain the balance with gravity pressing inward, the core compensates by shrinking and heating up
• C) as time progresses, more and more heat is trapped inside the core, leading to an increase in brightness
• D) as hydrogen is converted into helium in the core, the number of hydrogen nuclei decreases, decreasing the fusion rate. To maintain the balance with gravity pressing inward, the core compensates by expanding and cooling

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Definitions:

Direct Labor-Hours

Complete work hours of employees directly incorporated in production tasks.

Variable Overhead

Indirect production costs that vary with the level of production, such as electricity costs or materials used in the maintenance of machinery.

Manufacturing Overhead

All indirect costs associated with manufacturing, such as indirect materials, indirect labor, and other overhead costs.

Labor Efficiency Variance

The difference between the actual labor hours used and the standard labor hours expected, multiplied by the standard labor rate.