  We give explicit formulas for maps in a long exact sequence connecting
bialgebra cohomology to Hochschild cohomology. We give a sufficient condition
for the connecting homomorphism to be surjective. We apply these results to
compute all bialgebra two-cocycles of certain Radford biproducts
(bosonizations). These two-cocycles are precisely those associated to the
finite dimensional pointed Hopf algebras in the recent classification of
Andruskiewitsch and Schneider, in an interpretation of these Hopf algebras as
graded bialgebra deformations of Radford biproducts.
