A Rock Contains 0

question 102

Multiple Choice

A rock contains 0.313 mg of lead-206 for each milligram of uranium-238.The half-life for the decay of uranium-238 to lead-206 is 4.5 × 10⁹ yr.The rock was formed ________ years ago.

• A) 1.41 × 10⁹
• B) 1.08 × 10⁹
• C) 1.39 × 10⁹
• D) 2.00 × 10⁹
• E) 1.56 × 10⁹

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Definitions:

Express

To show, manifest, or reveal something through words, gestures, actions, or artistic expression.

Proportion

A portion, fraction, or quantity assessed in relation to its total entity.

Business

An organization or enterprising entity engaged in commercial, industrial, or professional activities.

Consumer Price Index

An index measuring the change in the price level of a basket of consumer goods and services purchased by households.