Variables between Quiz Question Slide - Has a student answered a question? - Submit all at once

GOAL

Letting students knowing when they have selected an answer to all questions before submitting a quiz, i.e., we will have prev/next buttons instead of submit on each question set.

POSSIBLE SOLUTION

Have an "answered" flag shown on the last quiz question slide which is locked to the bottom of the group that shows just that; either answered or not answered is shown dependent on if the question has an answer.

Is there anyone with experience doing this?