Look the picture beside especially in the section in red.
The number three position is slightly above the other letters. This position is called Superscript. It is often used especially in mathematics and physics calculation unit.
Menu Superscript in Microsoft Office Excel easier to find than on the Open Office. Although it still does not matter.
In Open Office, you should seek Format Character menu. To be more clear, follow the Youtube video tutorial below.
[SWF]http://www.youtube.com/watch?v=k_yTPVCzIkw, 425, 349[/SWF]