The Average Density of the Interstellar Medium Is

question 24

Multiple Choice

The average density of the interstellar medium is

• A) much denser than Earth's atmosphere.
• B) much less dense than the best vacuum on Earth.
• C) about the same density as air on the peak of Mount Everest.
• D) zero.
• E) about as dense as Earth's atmosphere at sea level.

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Definitions:

Circulatory System

The body's system responsible for transporting blood, nutrients, gases, and wastes to and from cells.

Spicules

Small, pointed structures made of calcium carbonate or silica found in sponges and some other invertebrates, serving as structural support and defense.

Tracheal Tubes

A system of small tubes in insects that carries oxygen directly to tissues and organs.

Exoskeleton

A rigid external covering that supports and protects the bodies of certain animals, such as insects, crustaceans, and some mollusks.