The susquehanna river, which runs through the states of new york, pennsylvania, and maryland, received the designation "america’s most endangered river" in 2005. one of the river’s problems results from the large number of sewage overflow sites that are found along the course of the river. these sewage overflow sites are a direct result of an increase in
a. global warming
b. recyling programs
c. human population
d. atmospheric changes

The correct answer is option c. "human population".

Explanation:

A lot of studies suggest that an increase of human population in most cities results in an increase on the amount of sewage on nearby rivers. If a large number of sewage overflow sites are found in the Susquehanna River it is very likely that is a direct result of an increase in human population. More people living in the cities of the states of New York, Pennsylvania, and Maryland would directly result in an increase in the sewage overflow of the river.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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