Peat and Various Grades of Coal Are Categorized Primarily By

question 20

Multiple Choice

Peat and various grades of coal are categorized primarily by:

• A) increasing hardness.
• B) increasing carbon and water content.
• C) decreasing molecular size, as carbon molecules break down.
• D) color scales, from light brown through jet black.

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Definitions:

Substitute Resources

Productive inputs that can be used instead of other inputs in the production process; resources for which an increase in the price of one leads to an increase in the demand for the other.

Complementary Resources

Productive inputs that are used jointly with other inputs in the production process; resources for which a decrease in the price of one leads to an increase in the demand for the other.

Backflows

In a systems context, refers to the reverse flow of a liquid, gas, or other substance, counter to the intended or normal direction, which can create issues such as contamination.

Skill Transferability

The ease with which people can shift their work talents from one job, region, or country to another job, region, or country.