The Diagram Below Illustrates the Radioactive Decay of Potassium (⁴⁰K)

question 21

Multiple Choice

The diagram below illustrates the radioactive decay of potassium (⁴⁰K) , which has a half-life of 1.3 billion years. If a lunar rock is found that currently contains 5 grams of ⁴⁰K, and it is determined that the sample contained 20 grams when it was formed, how old is the lunar rock?
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• A) 6.5 billion years
• B) 19.5 billion years
• C) 2.6 billion years
• D) 3.9 billion years
• E) 4.6 billion years

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Definitions:

Positive Reinforcement

A technique in behavior modification that involves rewarding a desired behavior to increase the likelihood of its occurrence.

Subordinate

An employee who reports to another employee higher in the organizational hierarchy, often tasked with carrying out specific jobs under supervision.

Staff Meeting

A regular gathering of employees led by management to discuss organizational issues, updates, and strategies.

Incentive Compensation Systems

Reward structures designed to motivate employees by tying a portion of their earnings to specific performance metrics.