Answer: the invention of cotton gin
Explanation:The cotton gin refers to a a machine that sets aside cotton fibers from their seeds. Therefore, the invention of the cotton gin transformed the cotton industry in the United States and demanded cheap labor force, which led to the rise of slavery in the South and to the American Civil War later.
In the United States and in other western democracies, the "Unwritten Constitution" includes the practice of "issuing currency," since this is not explicitly mentioned in the Constitution.
Two of the expected demands made by the Treaty of Versailles towards Germany are 1. Germany had to take sole responsibility for the war and 2. Germany had to lose much of its industrial areas.
