Consequences of Polynomial & QuasiPolynomial time algorithms for UP, FewP and CoC=P
1a) yes by the inclusion.
b) Not sure what you mean by "it". If P=PSPACE then A and B are both in P.

2a) Not necessarily, A could be much easier than B.
b) There are relativized worlds where P=FewP&lt;>NP.
c) No, RP^UP does not necessarily contain NP. Don't confuse UP with Promise-UP.