  Define z to be the smallest cardinality of a function f:X->Y with X and Y
sets of reals such that there is no Borel function g extending f. In this paper
we prove that it is relatively consistent with ZFC to have b<z where b is, as
usual, smallest cardinality of an unbounded family in w^w. This answers a
question raised by Zapletal. We also show that it is relatively consistent with
ZFC that there exists a set of reals X such that the Borel order of X is
bounded but there exists a relatively analytic subset of X which is not
relatively coanalytic. This answers a question of Mauldin.
