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.
No. It is similar only in that it is in the form of a dry stick. Chalk is composed of calcium carbonate mixed with silt and clay. It is white or generally light in color and much harder than pastel. Some chalk may, however, be used together with pigment to create paler tints of pastel.