What Do We Mean by the Main-Sequence Turnoff Point of a Star

question 61

Multiple Choice

What do we mean by the main-sequence turnoff point of a star cluster,and what does it tell us?

• A)It is the point in a star cluster beyond which main-sequence stars are not found,and it tells us the cluster's distance.
• B)It is the spectral type of the hottest main-sequence star in a star cluster,and it tells us the cluster's age.
• C)It is the luminosity class of the largest star in a star cluster,and it tells us the cluster's age.
• D)It is the mass of the most massive star in the star cluster,and it tells us the cluster's size.

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Definitions:

Hallucinogens

Substances that cause profound changes in perception, thought, and mood, often leading to visual or auditory hallucinations.

Depressants

Substances that reduce the activity of the central nervous system, leading to relaxation, reduced anxiety, and sleepiness.

Stimulants

Substances that increase arousal, attention, and energy by enhancing the activity of certain neurotransmitters in the brain.

Psychological Health

A state of well-being in which an individual recognizes their own abilities, can cope with the normal stresses of life, work productively, and contribute to their community.