A4 paper or ordinary homework paper, which is stronger?

Regarding whether there is a difference in hardness between a4 paper and plain paper, my answer is that there is no difference in hardness between a4 paper and plain paper. A4 paper, with only length and no specific paper, can also be understood as ordinary paper; In addition, a4 paper is a kind of paper commonly used in copying, mostly 80g double-sided adhesive paper, which also belongs to ordinary paper.