Which Component of the Milky Way Galaxy Accounts for Interstellar

question 111

Multiple Choice

Which component of the Milky Way Galaxy accounts for interstellar extinction, the dimming of light from distant objects?

• A) cool hydrogen gas
• B) so-called hidden or missing matter, since its absorbing properties render it invisible in the Galaxy
• C) molecules such as H₂ and CO, which are strong absorbers, in molecular clouds
• D) dust

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Definitions:

Defined Contribution Plan

A retirement plan where the employer, employee, or both contribute to an individual's account, and the retirement benefits depend on the account's investment performance.

Risk-free Return

The theoretical return on an investment with zero risk of financial loss, often represented by the yield on government securities.

Defined Contribution Plan

A retirement plan where both the employee and employer contribute to an account, with the final benefit dependent on account performance.

Risk-free Return

The theoretical return on an investment with no risk of financial loss, typically less than the return on riskier investments.