How do you unhide and hide rows and columns in excel 2007?

Ctrl - 9 hides a row. Ctrl - Shift - 9 unhides a row.

Ctrl - 0 hides a column. Ctrl - Shift - 0 unhides a column.
Ctrl - 9 hides a row. Ctrl - Shift - 9 unhides a row.

Ctrl - 0 hides a column. Ctrl - Shift - 0 unhides a column.