1. I'm not sure of the size of hole etc., but something like draw round a 5p piece and then have to pass a 2p piece thru' the hole without tearing.
The answer is to fold the paper across the hole then bend upwards in the other direction (in the plane of the paper) - bit difficult to describe.
2. How to support a weight e.g. a glass on a �10 note (or similar) over a 4" gap?
Answer is to crease it lengthwise in a zig-zag maybe 6 or 8 times - then slightly fanned out, with the plane of the zig-zags near vertical, it will support a fairish weight.
3. Then there's the silly one where you ask if anybody can throw a sheet of paper right across the room. You demonstrate with the paper completely flat as you ask.
The answer of course is to screw the paper into a ball and throw it.