The Earliest Metal Worked Systematically by Humans Was

question 9

Multiple Choice

The earliest metal worked systematically by humans was

• A) copper.
• B) tin.
• C) bronze.
• D) iron.
• E) steel.

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Definitions:

REM Behavior Disorder

A sleep disorder characterized by the acting out of dreams that are vivid, intense, and sometimes violent, due to a lack of muscle paralysis during REM sleep.

Medial Hypothalamus

An area of the brain involved in regulating hunger, thirst, and the body's energy balance.

REM Sleep

A sleep phase characterized by rapid eye movements, where dreaming occurs and brain activity is similar to wakefulness, important for processing emotions and memories.

Restorative Theory

A theory that suggests sleep is necessary for the body to repair and rejuvenate itself.