A Rock Contains 0

question 4

Multiple Choice

A rock contains 0.167 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)7.52 × 10⁸
• B)6.08 × 10⁸
• C)7.95 × 10⁸
• D)1.15 × 10⁹
• E)8.77 × 10⁸

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Definitions:

Implicit Costs

The opportunity costs of using resources owned by the firm for its project instead of selling or renting them to others.

Fixed Costs

Costs that do not vary with the level of production or output, such as rent, salaries, and insurance.

Variable Costs

Variable costs are expenses that change in proportion to the level of production or business activity.

Average Fixed Costs

The total fixed costs of production divided by the number of units produced, representing the fixed cost per unit of output.