I'm very sorry but I don't know where to put this because it's not really a task, merely something I thought of.
I recently heard about 3D 'angles' and how they function e.g. how you would describe a sphere shaped 3D radius.
However how would a 4D 'angle' look? I've been thinking about this and would it just look like a sphere inside a sphere or torus/doughnut? (ironic that the universe is hypothesized to be this shape :P)