1. interface DoStuff2 {2.   float getRange(int low, int high); }3.4. interface DoMore {5.   float getAvg(int a, int b, int c); }6.7. abstract class DoAbstract implements DoStuff2, DoMore { }8.9. class DoStuff implements DoStuff2 {10.   public float getRange(int x, int y) { return 3.14f; } }11.12. interface DoAll extends DoMore {13.   float getAvg(int a, int b, int c, int d); }