Long-Lasting Spiral Density Waves Occur in the Disk of a Spiral

question 56

Multiple Choice

Long-lasting spiral density waves occur in the disk of a spiral galaxy when

• A) the spiral merges with another galaxy.
• B) the galaxy is too close.
• C) the galaxy's disk is regularly disturbed.
• D) None of the above

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Definitions:

Diagnose

The process of identifying a disease, condition, or injury from its symptoms and signs through examination and testing.

Autopsy

A post-mortem examination of a body to determine the cause of death or the extent of disease, performed by a pathologist.

Delirium

A serious disturbance in mental abilities that results in confused thinking and reduced awareness of the environment.

Undetected

Pertains to something not being discovered or noticed, often used in medical or psychological contexts.