When Did the Level of Oxygen in Earth's Atmosphere Become

question 37

Multiple Choice

When did the level of oxygen in Earth's atmosphere become high enough to sustain aerobic respiration?

• A) 1.0 billion years ago
• B) 1.5 billion years ago
• C) 2.7 billion years ago
• D) 3.5 billion years ago

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Definitions:

California Unionized Supermarkets

Supermarkets in California that have their workforce represented by labor unions, impacting wage levels, working conditions, and labor-management relations.

Strikes

Work stoppages initiated by employees as a form of protest, typically aiming for better wages, conditions, or benefits from their employers.

U.S. Economy

The economic system of the United States characterized by a mixed economy that supports both private and public enterprises.

Pure Monopsony

A market condition where there is only one buyer for many sellers, giving the buyer significant power over prices and terms of sale.