Final answer:
Specific figures for cotton production in 1791 and 1801 are not provided, but South Carolina produced 6.5 million pounds by 1800. By 1860, the U.S. produced over two billion pounds of cotton, representing more than 60% of the country's exports.
Step-by-step explanation:
The question inquires about the amount of cotton produced by the United States in the years 1791, 1801, and 1860. However, specific data for 1791 and 1801 are not provided in the given reference material. Nonetheless, it is known from the sources that by 1800, the state of South Carolina produced 6.5 million pounds of cotton. Given the significant initiatives in the early 1800s to increase cotton production, it is plausible that the 1801 figures would be slightly higher than those of 1800. In contrast, by 1860, the American South, leveraging the labor of enslaved individuals, had drastically increased its cotton output, producing over two billion pounds of cotton, an amount making up more than 60 percent of the United States' total exports for that year.