A Green Card holder who is not a minor can file Form N-400, Application for Naturalization, to obtain US citizenship. Similarly, he must have become a permanent resident before five years and must have remained as a permanent resident in America for at least five long years.
Now, flat paint is (usually) a latex paint that dries without a reflective finish-that's it-the finish is smoother (imho) than chalk paint. Chalk paint really dries quickly and it has a rough texture to it after it dries. Many people use wax or poly-acrylic sealant on top of their furniture piece to keep the paint from peeling. So there ya go, my best explanation.
Acrylic and latex paint are somewhat similar as they are produced from acrylic resin. Once the acrylic and latex paints were produced, it replaced oil and alkyd paints. Though both paints are similar in some respects, they have many differences between them. When latex paint is more used for painting homes or other structures, acrylic is mainly used in artwork. Latex paint is available everywhere, and you can buy them from any hardware store or paint shop. On the other hand, acrylic paint can be bought mainly from craft stores.