Answer:
highly developed nation with an aging population
Explanation:
read carefully
Answer:
European settlers and Americans transformed the Great Plains from natural grassland to fields of corn.
Explanation:
The Great Plains are a vast portion of prairies with just a few trees. When worked correctly, it can be transformed into great fields for agriculture.
D. Hydrogen
Two elements make up the overwhelming majority of the sun's matter, by mass: hydrogen (about 70 percent) and helium (about 28 percent).
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