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

question 55

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:

SST Gel Tubes

Blood collection tubes containing a gel separator and clot activator used for serum separation in laboratory tests.

Venous Collection

A medical procedure involving the collection of blood from a vein, typically for testing purposes.

Blood Specimens

Samples of blood collected for medical examination or analysis.

Vacuum Method

A medical procedure or technique utilizing suction, commonly used in contexts such as childbirth (vacuum delivery) or abortion.