Questions handed in by students on 2015-12-02.

Lecture - 

1) To work out if A \subset X (CW complex) is open we check if \Phi_\alpha^{-1}(A) is open in D_\alpha^n.  What topology do we use on D_\alpha^n? 

2) Can we use CW complexes to compare presentations of groups?  e.g. < a, b | ab^2a^{-1} = b^3, ba^2b^{-1} = a^3 > is a 'bad' presentation of a well known group.  Can CW complexes be used to show which group it is? or give a 'simpler' presentation?