thanks for patience.
I guess I'm way behind on Sage knowledge. I do not understand what gets computed and checked internal to Sage and what and how variables get passed to Webwork. How about pointing me to the documents that discuss this and the terminology? For example, I have seen the term Sage cell but do not understand it or its implications. I probably thought I could work with examples, like I started with Webwork. Alas, this does not seem to be the case.