In the Above, Which Figure Represents Stars with the Longest Main-Sequence

question 4

Multiple Choice

In the above, which figure represents stars with the longest main-sequence lifetimes? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

• A) A
• B) B
• C) C
• D) D
• E) E

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Definitions:

Circadian Cycle

A natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.

Hypothalamus

A small region of the brain located below the thalamus that plays a crucial role in many essential functions, including hormone regulation, temperature control, and hunger.

Altered State

A condition of consciousness that is significantly different from one's normal waking state, often induced by substances, meditation, or hypnosis.

Consciousness

The quality or state of awareness, being aware of an external object or something within oneself, encompassing thoughts, feelings, and the environment.