Between 1860 and 1920, the Number of Mouths Fed Per

question 23

Multiple Choice

Between 1860 and 1920, the number of mouths fed per farmer

• A) decreased by about 10 percent.
• B) initially decreased, but then returned to its former level and remained there.
• C) increased by about 50 percent.
• D) nearly doubled.

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Definitions:

Platinum

A dense, malleable, ductile, and highly unreactive precious metal used in jewelry, automotive catalytic converters, and various industrial applications.

Mafic to Ultramafic Intrusions

The intrusion of magma rocks ranging from mafic (rich in magnesium and iron) to ultramafic (extremely rich in magnesium and iron) compositions, important in the formation of various ore deposits.

Veins

Mineral deposits that fill cracks in rocks, often distinguished by their different materials from the surrounding rock.

Hydroelectric Dams

Dams built to generate electricity by using the energy of water flowing through turbines.