The correct answer is acid rain.
Acid rain - characterized as containing harmful levels of sulfur dioxide or nitrogen oxide; acid rain is damaging and potentially deadly to the earth's fragile ecosystems; acidity is measured using the pH scale where 7 is neutral, values greater than 7 are considered alkaline, and values below 5.6 are considered acid precipitation; note - a pH of 2.4 (the acidity of vinegar) has been measured in rainfall in New England.
<em>CIA World Factbook Notes and Definitions
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<em>CIA World Factbook</em>
Answer: Social institutions are the social patterns directing human behaviour in the performance of basic activities. Social institutions provide better chances for human survival. The central aspects of institutions are the, functions and the roles carried out by their members.
Explanation:none