You can't ever be sure of anything. Thats just approaching something scientifically. But you can be pretty damn fucking sure of something. To a 99.999999999999999999999999%+ accuracy. I wouldn't call that being an agnostic.

I can answer 6 of these with a simple yes or no. Its funny how being the slightest bit scientifically literate turns "questions that we'll never solve" into questions a teenager could solve.