Leonora Corbett is about to go into action in "Park Avenue", the new Max Gordon musical. As wife number one, who meets wife number four and has to make up her mind whether to oust husband number four for husband number five, Miss Corbett, light as helium and twice as naughty, does a sophisticated job on the divorce racket. She is dressed for the part in a white shirt and red crepe skirt slit at vital spots to reveal her famous legs. In her spare time Miss Corbett is campaigning for the United Hospital Fund's annual drive.