Answer
$-a^2b+ab^{2}-b^{3}$
Work Step by Step
Using the Distributive Property, the product of the given expression, $
-b(a^2-ab+b^2)
,$ is
\begin{array}{l}\require{cancel}
-b(a^2)-b(-ab)-b(b^2)
\\\\=
-a^2b+ab^{1+1}-b^{1+2}
\\\\=
-a^2b+ab^{2}-b^{3}
.\end{array}