If this (²) is how you make a "2" small and rrze above a "m" m2, how do you make a "mm" rize above a number
The code you reference is a specific short code html entity, there isn't a version of that for everything. What you're looking for is called "superscript".
The good part is you really don't need to use short codes for everything superscripted. The best way to do superscript is to combine the <sup> html tag with css...
In your css, add this...
sup {
position: relative;
top: -1ex;
vertical-align:baseline;
font-size: 80%;
}
In your html, any text you want to be superscript, add <sup></sup> tags around it, like this...
<p>Here is some pure text awesomeness<sup>10</sup> (text awesomeness to the power of 10)</p>
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