Well, this is a broad question, so I'm not quite sure what answer you're looking for, but the simplest answer, which used to get me confused, is: the monomer is a repeat unit of the polymer. Let's start by analyzing the words monomer and polymer. Mono = one, and poly = many. Now, lets go back to the science.
History of the United States with 150+ answers. According to one source: Twelve American presidents owned slaves, eight while serving in office, and at least 25 presidents count slave owners among their ancestors.. http://www.slate.com/articles/li... However, to put this into perspective this would be 37 that were either slave owners themselves or descended from slave owner ancestors - or 84%.
How did Jefferson acquire his slaves? Jefferson acquired most of the over six hundred slaves he owned during his life through the natural increase of enslaved families. He acquired approximately 175 slaves through inheritance: about 40 from the estate of his father, Peter Jefferson, in 1764, and 135 from his father-in-law, John Wayles, in 1774.