Final Q2: The concept of "field expression" is subject to ambiguous interpretation

The phrase “field expression” does not exist in Mongo Documentation; at least I can’t find it.

May I suggest you change to “an expression which resolves to a field”? Or something else less ambiguous.

@RalphTamlyn

If you feel the question can be improved, I’d strongly suggest using the “Report an issue” tab at the bottom of the page to make that comment. That goes directly to the curriculum team, while these Forum posts are not normally reviewed by them. Good luck.