Given 11. class Alpha ( 12. public void foo) { System.out.print( Afoo ");) 13. 14. public class Beta extends Alpha f 15. public void foo) { System.out.print("Bfoo ");) 16. public static void main (String[l args) { 17. Alpha a new Beta); 18. Beta b (Beta)a, 19. a.foo0 20. b.foo) 21. 22.1 What is the result