Bob,
Delete and Backspace are treated as variations of the same command. While Backspace continues to work for the previous character, "Num+Backspace" works as "Delete" to delete a number of different things, including crashed apps. Thus "Ctrl+Alt+Del" becomes "Ctrl+Alt+Num+Bkspc".
In general, the dedicated Editing function keys become shift variations on the cursor arrow keys, e.g., Sym+Up Arrow = Page Up. A quick-reference label is provided for these combinations.
John Parkinson
New Standard Keyboards