If Early Earthʹs Atmosphere Contained Little or No O2, Then

question 13

Multiple Choice

If early Earthʹs atmosphere contained little or no O2, then where did most of the O2 in our modern atmosphere come from?

• A) Respiration
• B) The splitting of water vapor by sunlight
• C) The breakdown of carbon dioxide
• D) Photosynthesis
• E) The oxidation of metals

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Definitions:

Negotiation

Negotiation is a dialogue between two or more people or parties intended to reach a beneficial outcome over one or more issues where a conflict exists with respect to at least one of these issues.

Walk Away

The act of leaving or disengaging from a situation or negotiation, especially when an agreement or resolution cannot be achieved.

Communicate

The process of conveying information or expressing thoughts and ideas in a way that is understandable to others.

Questioning

The act of asking for information or clarification to understand something more deeply.