Why Is the Texture of the Igneous Rock Obsidian Glassy

question 19

Multiple Choice

Why is the texture of the igneous rock obsidian glassy?

• A) Obsidian commonly forms at the surface of lava flows.
• B) Obsidian always forms beneath the earth's surface.
• C) Obsidian is aphanitic.
• D) Obsidian is phaneric.

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Definitions:

Total Utility

The total satisfaction received by a consumer from consuming a certain amount of a good or service.

Marginal Utility

The change in satisfaction or utility derived by consuming an additional unit of a good or service.

Indifference Curves

Indifference curves are graphical representations used in microeconomics to show combinations of two goods among which a consumer is indifferent, reflecting their preferences and consumption choices.

Marginal Utility

The change in satisfaction or utility that a person receives from consuming an additional unit of a good or service.