How Did Oxygen (O₂)get into Earth's Atmosphere

question 63

Multiple Choice

How did oxygen (O₂) get into Earth's atmosphere?

• A)It was captured from the solar nebula.
• B)It was outgassed from volcanoes.
• C)It came from chemical reactions with surface rocks.
• D)It was released by life through the process of photosynthesis.

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Definitions:

Apprenticeship

A system of training a new generation of practitioners of a trade or profession with on-the-job training and often some accompanying study.

Journeyman Welder

A skilled welder who has completed an apprenticeship and is fully qualified to work in the welding field.

Trade School

A vocational institution designed to teach students skills for a specific job or career.

Behavior Modeling

A training technique that involves demonstrating desirable behaviors and allowing learners to practice and mimic these behaviors.