We Have Found That the Upper Layers of the Mantle

question 588

Multiple Choice

We have found that the upper layers of the mantle are "plastic." Why is this important?

• A) Plastic is an important resource for the future.
• B) These layers can easily crack to allow pent-up heat and energy to escape.
• C) These layers can easily bend to accommodate oceans and mountains.
• D) The continents are able to float and drift on these layers.

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Definitions:

Income Security

Financial protection against uncertainties causing loss of income, including programs like pensions, unemployment insurance, and social security.

National Defense

Government or collective actions and strategies intended to protect a country and its citizens from external threats and maintain territorial integrity and sovereignty.

Opportunity Cost

The amount of other products that must be forgone or sacrificed to produce a unit of a product.

Government Deficits

The financial shortfall when a government's expenditures exceed its revenues.