What one thing were colonist more afraid of
than a black uprising and what did they do
about it?

First off slave rebellions were a continuous source of fear in the American South, especially since black slaves accounted for more than one-third of the region’s population in the 18th century. Laws dictating when, where and how slaves could congregate were enacted to prevent insurrection and quell white paranoia. It’s estimated there were at least 250 slave rebellions in America before slavery was abolished in 1865.

Explanation:

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b) the planets year length would be longer

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