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.
P waves is moved by compressing and expanding.
S waves is form perpendicular angle when they pass.
For continental U.S. the answer is never. Since the earth's rotation axis is tilted 23.5 degrees with respect to its orbital motion around the su, one would have to be less than 23.5 degrees above or below the equator to have the sun pass direclty overhead
Tokyo/Yokohama is city with the largest population in the world. It has over 33 million people.
