When written with a number the degree symbol is interpreted to apply to the number. The following letter (F or C) is an abbreviation and must be separated from the number (and degree sign) by a space. The letter is then punctuated in literary mode as an abbreviation. If there is no number, the degree sign applies to the letter. A dot 5 brings the braille back to the baseline and the expression is punctuated in mathematical mode. Did I just confuse the issue? Hope not.