Trying to Capture Blank Response

I am working on a “Directions Quiz” in which the directions say to not answer any of the questions and then at the end there is a success (A+) or fail based on if they followed the directions. So I am ultimately wanting to only count blank math input boxes - if they type anything (right or wrong) in the the math input box, then the question is wrong. I’ve tried CLD with correct response valued at 0 and then at the end if the result was >0 then they had success but that doesn’t work if they type in the wrong answer. I’ve tried many different combinations and in every combination I get most of it to work but keep coming up with one combo that will result in the opposite result than what I want. I know this sounds confusing and I hope it will make sense if you look at my activity: Pop Quiz • Activity Builder by Desmos

This copy has them answering only question 1. I would prefer that they not answer any questions. Let me know if I can provide additional information.

Thank you in advance!!!

The isBlank boolean might be what you are looking for…

https://teacher.desmos.com/computation-layer/documentation#function:isBlank