In 1971, What Occurred for the First Time in the Twentieth

question 59

Multiple Choice

In 1971, what occurred for the first time in the twentieth century?

• A) China held free elections.
• B) Vietnam had no outside country ruling it.
• C) Personal computers outsold televisions.
• D) Cell phones started to replace landline phones.
• E) The United States had a merchandise trade deficit.

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Definitions:

Metal-rich Fluids

Liquids emanating from the Earth's crust, usually heated by magma, that are high in dissolved metals, often found in volcanic and hydrothermal areas.

Magma

A molten rock material beneath the earth's surface, which can solidify to form igneous rocks.

Deep Canyon

A profound and narrow valley with steep sides, carved by a river, glacier, or geological processes over time.

Permeable Rocks

Rocks that allow water to pass through them due to their porous nature.