Scheduled to graduate June 3 from the U.S. Naval Academy at Annapolis, Md., is Midshipman First Class ROBERT L. PRENDERGAST, son of Ferdinand M. Prendergast, 2218 avenue P, and Mrs. Naomi M. Prendergast of Miami. Fla. Upon graduation, Prendergast, will receive a bachelor of science degree and be commissioned an ensign in the United States Navy. He entered the Naval Academy on a competitive appointment in June, 1955, after graduating from Coral Gables, Fla., Senior High School and