An Ancient Rock Is Found to Contain ⁴⁰Ar Gas,indicating That

question 66

Multiple Choice

An ancient rock is found to contain ⁴⁰Ar gas,indicating that of the ⁴⁰K in the rock has decayed since the rock solidified.Any argon would have boiled out of liquid rock.The half-life of ⁴⁰K is 1.25 billion years.How long ago did the rock solidify?

• A) 2.6 billion years
• B) 0.50 billion years
• C) 1.8 billion years
• D) 0.30 billion years

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Definitions:

Unrealized Increase

An increase in the value of an asset or investment that has not been sold or exchanged, meaning the gain is not yet reflected in income.

Allowance

In accounting, an estimate for future adjustments to assets, such as bad debt or depreciation.

Market Value

The current price at which an asset or service can be bought or sold in a public marketplace.

Realized Gains

Profit from the sale or exchange of an asset that exceeds its purchase price.