Can somebody please help a brainlet with the following?

I'm trying to figure out of each of these is open, closed , both, or neith and understand why?

1. The set [0,1] x {1} U {1} x [0,1] in th unit square [0,1]x[0,1] with subspace topology inherited from Sorgenfrey plane

2. The set {1/2} x [0,1] in the unit square with order topology (where square has lexicorgraphical order)

3. Again {1/2} x [0,1] in unit square with subspace topology inherited from R^2 with order topology (where the plane has lexicographical order)