Dark Matter Suspected to Exist in the Universe Because

question 32

Multiple Choice

Dark matter suspected to exist in the universe because:

• A) the night sky is dark between stars
• B) the orbital period of stars in the outer parts of a galaxy is greater than the orbital period of stars near the galactic center
• C) the orbital period of stars in the outer parts of a galaxy is less than the orbital period of stars near the galactic center
• D) the orbital period of stars in the outer parts of a galaxy is about the same as the orbital period of stars near the galactic center
• E) all galaxies have about the same mass

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Definitions:

Developmental Level

The stage of growth or progression in physical, emotional, intellectual, or social development typical for a certain age or group.

Superego

In psychoanalytic theory, the part of the personality responsible for the internalization of societal and parental standards of conduct, operating on the morality principle.

Fixation

According to Freud, a condition in which the id, ego, and superego do not mature properly and are frozen at an early stage of development.

Libido

The sexual energy that fuels the id.