When Did Life First Appear on Earth

question 17

Multiple Choice

When did life first appear on Earth?

• A) 14 billion years ago
• B) 400 million years ago
• C) 4.6 billion years ago
• D) 65 million years ago
• E) 3.4 billion years ago

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Definitions:

Minimum ATC

Minimum ATC, or minimum average total cost, is the lowest point on the average total cost curve, representing the most efficient scale of production for a firm.

Entry Barriers

Obstacles that make it difficult for new competitors to enter a market, which may include high capital requirements, brand loyalty, or regulatory policies.

Marginal Costs

The cost of producing one additional unit of a good or service.

Profit-Maximizing

The process by which a company determines the price and output level that returns the greatest profit.