Why Is the Major Branch of the K- 40 Decay

question 16

Multiple Choice

Why is the major branch of the K- 40 decay to Ca- 40 not useful in most cases for whole rock dating?

• A) It only works 89% of the time.
• B) Ca- 40 is itself unstable and further decays to more daughter products.
• C) The Ca- 40 that is produced by decay is indistinguishable from the naturally most abundant isotope of Ca that may have been present initially.
• D) The decay to Ar- 40 is faster and has wider geologic applicability.

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Definitions:

Mixed Costs

Expenses that have both fixed and variable components, changing in total with the level of activity but not in a directly proportional manner.

Selling and Administrative Expenses

Costs related to the selling of products and the managing of the company, excluding production costs.

Contribution Margin

The amount of revenue remaining after deducting variable costs, contributing towards covering fixed costs and generating profit.

Selling Price

The price the customer pays for a product or service.