a) Slavery increased in the South due to the economic gain of cotton
Growing more cotton meant an increased demand for slaves.
Erie Canal was the one that was built to connect Albany and Buffalo
South Pass<span> is the lowest point on the Continental Divide between the Central </span>Rocky Mountains<span> and the Southern</span>Rocky Mountains<span>. The </span>passes<span> furnish a natural </span>crossing<span>point of the </span>Rockies<span>. The historic </span>pass<span> became the route for emigrants on the Oregon, California, and Mormon </span>trails<span>to the West during the 19th century.
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