The heading says it all, but let me explain it a little further.
Suppose you hang a sheet of paper (A4 size) from one end leaving the other end free. Now practically it seems impossible to punch a hole through it, but is this theoretically possible? Assume you can not use a bigger size of paper.
So is it theoretically possible to punch a hole in a suspended sheet of paper? Now, how will the size of the paper affect the result?
I am talking about punching with the hand and not anything else.