How can I get a cell to give required warnings if other cells are out of range.

Warnings to show in Cell M8.

Cells B8= 1960 C8= 1860 B39= 81 . I need cell M8 to show 1 of 3
statements.
Statement 1 if C8 is greater than B8 less 100, show. Check lenght.
Statement 2 if C8 is less than B9 less 100 but greater than B39, show.
Lenght OK.
Statement 3 if C8 is less than B39, show. Check length/depth.
Statements 1 & 3 to be in red and statement 2 to be green.
Thanks
Chris