The Substance Shown in the Figure Must Be a Solid

question 36

True/False

The substance shown in the figure must be a solid because you cannot see through it. ©Jim Birk

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Definitions:

REM Sleep

Rapid Eye Movement sleep, a stage of sleep characterized by rapid movement of the eyes, low muscle tone, vivid dreams, and increased brain activity.

Narcolepsy

A sleep disorder marked by excessive daytime sleepiness, often accompanied by sudden muscle weakness or sleep attacks.

REM Rebound

The tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep).

Insomnia

Insomnia is a sleep disorder characterized by difficulty falling and/or staying asleep, affecting a person's ability to get restful sleep.