What element that is the primary cause In. Pollution of Great Lakes

Heavy industry, manufacturing and agriculture are three of the major causes of pollution of the Great Lakes system. The production of persistent organic pollutants (POPs) such as PCBs, DDT and dioxins, had previously been of principal concern.

Explanation:

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in 342 bc j._c. egypt fell into the hands of the persians, under the reign of nectanebo ii

greek city-states unite in a revolt against the persian empire at the beginning of the fifth century bc. j.-c  

from the year 660 or 659 bc ad, cyrus preached the revolt against the medes to deliver the persians.

the answer to this question is d