An Ancient Rock Is Found to Contain ⁴⁰Ar Gas, Indicating

question 1

Multiple Choice

An ancient rock is found to contain ⁴⁰Ar gas, indicating that 77% 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:

Proceeds

Something that is exchanged for a debtor’s sold collateral.

Secured Party

A lender or creditor who has an interest in the collateral securing a loan or credit agreement.

UCC

Short for Uniform Commercial Code, it is a comprehensive set of laws governing all commercial transactions in the United States.

Collateral

Collateral refers to properties or assets that a borrower offers to a lender as security for a loan or credit, and that can be taken by the lender if the borrower fails to pay back the loan.