There are others but the main idea on many of them is to have Sage provide a nice picture (as WW can't) and to perhaps create the correct answer to check against based upon the WW input. I have a few which actually incorporate a live Sage cell inside the problem with which the student can actually complete their calculations or do whatever.

Many of these questions are available in github and are in the OPL. Directly from github: https://github.com/openwebwork/webwork-open-problem-library/tree/master/OpenProblemLibrary/MC/Sage . You can follow the director search in the library to find them as well so long as your system is up-to-date. You will need the sage.pl macro which is also available at https://github.com/openwebwork/pg/tree/master/macros .