Coal-burning factories and increased automobile usage has caused the greatest increase in "<span>A) air pollution," since in fact coal when burned is one of the worst pollutants. </span>
The answer is B. Without the United States, the League lacked the firepower to actually make a huge difference without the individual nations suffering huge consequences. In turn, the League didn't do anything, thus they were ineffective and nothing but a figurehead for democracy and international peace.
Answer: The domestic slave trade, also known as the Second Middle Passage and the interregional slave trade, was the term for the domestic trade of slaves within the United States that reallocated slaves across states during the antebellum period.
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