What Is the Age in Years of a Mineral Sample

question 7

Multiple Choice

What is the age in years of a mineral sample that has a mass ratio of ⁴⁰Ar to ⁴⁰K of 0.330? Potassium-40 decays to argon-40 with a half-life of 1.27 × 10⁹ yr.

• A)3.85 × 10⁹
• B)5.23 × 10⁸
• C)1.77 × 10⁹
• D)3.62 × 10⁸
• E)2.55 × 10⁹

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Definitions:

Money-Supply Curve

A graphical representation showing the relationship between the quantity of money in an economy and its price or interest rate.

Interest Rate

The proportion of a loan that is charged as interest to the borrower, typically expressed as an annual percentage of the loan amount.

Equilibrium

A situation in which the market price has reached the level at which quantity supplied equals quantity demanded.

Money Demanded

The total amount of money that households and businesses want to hold at a given time, often influenced by interest rates, income levels, and the economic outlook.