When defining the unit of measurement for a requirement, you may sometimes need superscript or even subscript. Think of m2 for the size of a space, for example.
To get superscript, place a letter between two ^ symbols.
So, m^2^ becomes m2
If you want subscript, place a letter between two ~ signs.
So, H~2~0 becomes H2O
Please note: you can use the super/subscript in all fields related to requirements.