How Do We Know That the Atmosphere of the Earth

question 23

Essay

How do we know that the atmosphere of the earth experienced an increase in O₂ and became oxidizing between 2.5 and 2 billion years ago?

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Definitions:

Horizontal

Referring to a direction or plane parallel to the ground or base line, at a right angle to the vertical.

Sketch Graph

The process of drawing a rough graph of a mathematical function or equation based on its key features, without the use of precise calculations.

Absolute Value

The distance of a number from zero on a number line, without considering direction.

Equation

An equation is a mathematical statement that asserts the equality of two expressions, often including variables and constants.