Which of the Following Best Describes Oxygen (O2)

question 161

Multiple Choice

Which of the following best describes Oxygen (O2) ?

• A)It is a gas which principally originates from volcanic sources.
• B)It is a by-product of photosynthesis.
• C)It is one of the gases from Earth's earliest atmospheres.
• D)It is now measured at 78.084% by volume in the homosphere.

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Definitions:

Insomnia Disorder

The most common sleep disorder in older adults, with nocturnal symptoms of difficulty falling asleep, frequent awakenings, shortened sleep, and non-restorative sleep, and daytime symptoms of fatigue, sleepiness, depression, and anxiety. DSM-IV diagnostic criteria require the symptoms to persist for at least one month, to be perceived as stressful, and to not be secondary to any other disorder.

Hypersomnolence

A condition characterized by excessive daytime sleepiness or prolonged nighttime sleep, not explained by other medical or psychiatric conditions.

Somnambulism

Also known as sleepwalking, a disorder that involves getting up and performing activities while in a state of sleep.

Drug Therapy

The use of prescribed pharmaceuticals to treat or manage mental health conditions or diseases.