Answer:
1991, because that is when the Soviet Union began producing fewer nuclear weapons.
Explanation:
OR C
Answer:
The United States has a good amount of freshwater supply over most of the territory, because the American territory is ripe with lakes, rivers, streams, and groundwater.
The quality of these water sources varies from area to area, and many water bodies have been deeply polluted by human activity. However, the United States is a developed country with generally good water treatment facilities.
Notwithstanding, the United States faces two important challenges: one is the growing population of the country, which will put more pressure on freshwater sources in the future. The other one is that a few areas of the country are devoid of water supply sources, and they are among the fastest growing regions of the U.S (Nevada, Arizona, New Mexico). This poises a great challenge for U.S. authorities in the near future.
Answer:
True
Explanation:
The model of the universe developed by Nicolas Copernicus gave better predictions than the model of Ptolemy. The model of Ptolemy had prevailed for centuries, and it placed the Earth at the center of the universe. However, Copernicus accurately established that the sun was located at the center of the solar system. Moreover, Copernicus also established that the Earth is only one of many planets, that the Sun is stationary and that the Earth moves in three different ways (daily, annual, and annual tilting), among other astronomical principles.
Answer:
They are weather systems that happen to spin in a counterclockwise direction in the Northern Hemisphere from low pressure points. They form between two big cold fronts when their temperatures are very different compared to each other. These air masses will blow past each other in opposite directions when it is formed.
