A cause was that Texas declared its independence from Mexico. It changed the U.S. by the U.S. gaining California, New Mexico, Utah, Arizona, Colorado and parts of Wyoming.
I'm pretty sure it's c that's what i'm getting it says farmers and other were going to march across the country and eat green corn for food is where the name came from but they attempted to enforced the drafts
The Battle of Gettysburg was pretty much when people realized the South was going to lose.
At the time of founding for the 13 colonies, slavery was legal in every one of them.