The Diagram Illustrates Physical Size and Angular Size as Seen

question 25

Multiple Choice

The diagram illustrates physical size and angular size as seen by the observer. We can estimate the size in light years (or parsecs or km) of M31 from

• A) its angular size in degrees.
• B) its distance in light years (or parsecs or km).
• C) both answers A and B
• D) It is impossible to estimate the size of M31.

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Definitions:

Endorphins

Natural, pain-killing chemicals released in the brain that also contribute to sensations of pleasure or well-being.

Enkaphalins

Peptides found in the brain, acting as neurotransmitters or neuromodulators, involved in regulating pain and emotion.

Neurons

Neurons are the basic working units of the brain and nervous system, specialized cells designed to transmit information to other nerve cells, muscle, or gland cells through electrical and chemical signals.

Skeletal Muscles

Muscles that are attached to bones and are responsible for voluntary movements of the body.