Implement a different font for text annotations in exercises

I agree that the font is hard to read and the lack of math formatting (such as LaTeX) make it less useful.  Please change the annotation font, and maybe add LaTex.

I also get frustrated annotations go away when I want to type the answer, so I have to either remember the answer or record it elsewhere.  (I recognize that the annotations would have to be behind the area where the answer is selected or typed, but surely that would be doable.)  Please let the annotations stay on the screen while giving the answer!