Take an unblushing look at nudity in art at the Smithsonian American Art Museum. Highlights include a tempting she-devil, an Eve who’d get you to bite an apple, a giddy drinker, native men with no need for a gym, a “topless” horseman, and a nude that gives new meaning to the word “hot.” Plus, you’ll dip a toe into the adjoining National Portrait Gallery to learn the salacious secrets of some rakish presidents and other famous Americans. No knowledge of art, or nudity, is required.