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:

German Servants

Individuals of German origin who worked as indentured servants, often in the Americas, agreeing to a fixed term of unpaid labor in exchange for passage to the New World, food, accommodation, and eventual freedom.

Frontier Settlers

Individuals or families who moved to the edge of settled territories to establish a new life, often facing harsh conditions and conflicts with indigenous people.

Anti-Federalists

Opponents of the ratification of the U.S. Constitution in 1787-1788, who favored stronger state governments and feared a too powerful federal government.

Proclamation of 1763

Royal directive issued after the French and Indian War prohibiting settlement, surveys, and land grants west of the Appalachian Mountains; caused considerable resentment among colonists hoping to move west.