Moving check work boxes after stated units is one of the primary reasons I use sectionWideCheckWork. You made it so that I can put those on an individual p tag, which means I can use them when there is in fact only one answer box in the “section.” I usually use the words and not the symbol for units so it looks a little weird, but
<p sectionWideCheckWork>
<answer><label><m>\sin^{-1}(0)=</m></label>0</answer><m>^{\circ}</m>
</p>
produces
