Thanks. Here is an example in HTML.
I've also done some re-formatting of answer entry in many of these so that the problem looks good when "static": either in print, or in HTML before it's activated. (Aesthetically I find it's better if the answer blanks only appear once the question is activated.)
The original is at Library/NAU/setLinearAlgebra/span.pg in the OPL.
In the original, you can see that the answer entry area is quite prominent. In the textbook context, this isn't desirable.
So in my version, you can see that until you "activate" the question, it appears to be a regular textbook-style question.
The answer blanks (and instructions for how to enter the matrix) don't appear until the question is activated.
Since I did most of my editing work on my server, this problem is now in my PreTeXt source as
<webwork source="local/Library/NAU/setLinearAlgebra/span.pg" />,
so the original path is preserved.
It would be easy enough for me to keep the original directory structure for all updated problems, so that it's clear where they came from.
I kept the original metadata intact, except for adding a line indicating that I edited it.