What made the battle of antietam the single bloodiest day in american history?

What did the us civil rights movement gain new momentum after world 2

What does the document of the birtish octopus is an uderlying cause of the world war 1

Why was galileo galilei brought before the inquisition? for insisting that earth stands still at the center of the universe for proving that planets move in elliptical orbits for putting forth evidence that earth moves around the sun for suggesting that the sun is a star