Answer:
have fallen by more than one-half.
Explanation:
Thick, noticeable smog in many of the cities and manufacturing centers of the United States helped bring the 1970 e Clean Air Act to spur passage at the height of the national environmental movement. The ensuing modifications were intended to enhance its effectiveness and address newly recognized problems of air pollution such as acid rain and stratospheric ozone layer damage. The Clean Air Act allows EPA to set national environmental air quality levels for certain specific and prevalent contaminants, based on the latest research, to protect public health and welfare nationally. Certain main regulations are intended to reduce the rise in emissions from increasing motor vehicle numbers and new manufacturing plants.
D) the English language is constantly changing and evolving
He was interested in a sepreatist movement for blacks. He wanted them to have their own nation, government and all. He wanted reperations for Africa, for slavery, although slavery was/is still advocated by many nations.
Fertile soils on the island are crucial for growing agricultural products that make up some of Hawaii's top exports. Although the islands are traditionally synonymous with pineapples and sugar, the U.S. Census Bureau lists Hawaii's primary exports as cocoa, macadamia nuts, papayas and coffee.
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