Approximately When Did the Earth's Crust Solidify

question 30

Multiple Choice

Approximately when did the earth's crust solidify?

• A)8 billion years ago
• B)4 billion years ago
• C)1 billion years ago
• D)4 million years ago

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Definitions:

Depletion

The allocation of the cost of natural resources over their useful life, reflecting the consumption of the resource.

Metal Ores

Naturally occurring minerals from which metals can be extracted economically.

Amortization

Amortization refers to the process of gradually writing off the initial cost of an asset over a period.

Expense Account

An account that records the costs of operating a business.