(MONEY Magazine) – YOUR MARCH ARTICLE "THE BEST JOBS in America" did not mention the rapidly growing profession of physician assistant (P.A.). The Department of Labor projects that the P.A. profession will experience annual growth rates of more than 23% through the year 2000. Starting annual salaries are $40,000 to $45,000 for new graduates. The average annual salary for a P.A. is $53,000. Bill Plymale Beatrice, Neb.