Hey guys I just want to check if my solution to an easy Hatcher exercise is correct (it's just i'm confused buy all the gluing stuff). P.91 he wants us to show that when you quotient EG (built as a delta complex) by G you get a covering. I'm just showing that it is free (that's obvious) and the action is proper (with the discrete topology on G) because a compact subspace K crosses at most a finite number of cells (idk if they are called like that as for CW-complexes, i just mean the open image of one of the maps delta^n->EG), and then it's a matter of easy combinatorics to show that gK intersects K for at most a finite number of g. Is that it? Thanks