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Factories, animals, and human are polluting water sources; people upstream pollute water for people downstream.
A steep slope or long cliff that separates two relatively level areas of differing elevations.
The total market value of all the goods and services produced within the borders of a nation during a specified period. (Gross Domestic Product)
Evidence taken from the spoken words of people who have knowledge of past events and traditions.
A group of relatives, such as those of three generations, who live in close geographic proximity rather than under the same roof.
A policy of racial segregation, practiced in the Republic of South Africa, involving political, legal, and economic discrimination against nonwhites.
The extension of voting privileges to all adults, without distinction as to race, sex, belief or social status.
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