Why Do O- and B-Type Stars Have Weaker Hydrogen Absorption

question 56

Multiple Choice

Why do O- and B-type stars have weaker hydrogen absorption lines than A-type stars?

• A) O- and B-type stars are cooler than A-type stars.
• B) O- and B-type stars are smaller than A-type stars.
• C) A larger fraction of hydrogen atoms in O- and B-type stars is ionized.
• D) O- and B-type stars have converted much more of their hydrogen into heavier elements.
• E) A-type stars have a higher mass than O- and B-type stars, so they have more hydrogen.

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Definitions:

Permanent Accounts

Accounts on the balance sheet whose balances are carried over into the next accounting period.

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A list of all company accounts that remain after adjusting entries and closing entries have been made, used to test the balance of debits and credits.

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Accounts that represent amounts owed to creditors or bills that must be paid in the future, contributing to a company’s liabilities on the balance sheet.