How Much of a Radioactive Parent Isotope Will Remain After

question 16

Multiple Choice

How much of a radioactive parent isotope will remain after three half-lives have passed?

• A) one-third
• B) three-halves
• C) one-eighth
• D) one-sixth

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Definitions:

Thousand Cubic Feet

A unit of measure used primarily in the United States for volume, often in reference to the consumption or production of natural gas.

Natural Gas

A fossil fuel used as a source of energy for heating, cooking, and electricity generation, composed mostly of methane.

Mcf

A standard measurement of natural gas volume, equivalent to 1,000 cubic feet.

Cash Flow Analysis

A detailing of how money comes in and how money goes out over a fixed period of time.