Suppose You Find a Rock That Contains 10 Micrograms of Radioactive

question 117

Multiple Choice

Suppose you find a rock that contains 10 micrograms of radioactive potassium-40, which has a half-life of 1.25 billion years. By measuring the amount of its decay product (argon-40) present in the rock, you conclude that there must have been 80 micrograms of potassium-40 when the rock solidified. How old is the rock?

• A) 3.75 billion years
• B) 1.25 billion years
• C) 2.5 billion years
• D) 5.0 billion years

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Definitions:

Inventory

A company's merchandise, raw materials, and finished and unfinished products which have not yet been sold.

Analytical Techniques

A broad range of methods and tools used to evaluate and interpret data for decision-making and problem-solving purposes.

NPV

Net Present Value (NPV) is a financial metric used to evaluate the profitability of an investment or project, calculated by summing the present values of incoming and outgoing cash flows.

Cost of Capital

The rate of return that a company must pay on its investments to satisfy its shareholders or debt-holders.