A strict question of fact has an answer determined solely by the state of the material universe, and sufficiently straightforward math, in a clearly understandable way—none of our uncertainty about this question is about definitions, values, or viewpoints; we are just wondering which quarks go where.
Questions of strict fact:
What happens if I press the giant red button?(*)
Did Sally claim more charitable donations as an income tax deduction than Bob?
Are there unicorns anywhere on Earth?
Will Peano arithmetic prove a contradiction if I search all the proofs less than a billion steps long?
Questions not yet of strict fact:
Should I press the giant red button?
Is Sally a more charitable person than Bob?
Do unicorns exist?
Will Zermelo-Frankel set theory prove a contradiction if I search for one forever?
Why the second group aren’t yet questions of strict fact:
Because the notion of should has not yet been fully specified or determined.
Because we haven’t said exactly what it means to be charitable.
Because “exist” is a much more ambiguous notion than “exist inside our galaxy”. For example, there could be unicorns lightyears away, or inside some other mathematical universe that has as much “existence” as this one does. The notion of “X exists” is less firmly nailed down than “X is inside our closet”.
Because the notion of ‘forever’ is more mathematically fraught than ‘for ten to the billionth power years’. For example, nailing down exactly which infinity we’re talking about can’t be done in a system of first-order logic.
(*) At least, this is a straightforward question so long as we don’t poke too hard at the nature of what-if counterfactuals. In most real-life situations, the question “What happens if I turn on this blender with a fork inside?” is something that has a sufficiently straightforward material answer for us to say that it’s just a question of material facts.