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I wonder how we know this for certain? Could you convince us that this is always the case, Arjun?
You have been given three shapes made out of sponge: a sphere, a cylinder and a cone. Your challenge is to find out how to cut them to make different shapes for printing.
This article for students gives some instructions about how to make some different braids.
This article for pupils gives an introduction to Celtic knotwork patterns and a feel for how you can draw them.