Answer
$a)$ $b^{14}$
$b)$ $12xy^{8}$
Work Step by Step
$a)$ $(a^{2})^{-3}(a^{3}b)^{2}(b^{3})^{4}$
Evaluate the powers:
$(a^{2})^{-3}(a^{3}b)^{2}(b^{3})^{4}=(a^{-6})(a^{6}b^{2})(b^{12})=...$
Evaluate the products:
$...=a^{-6+6}b^{2+12}=a^{0}b^{14}=b^{14}$
$b)$ $(3xy^{2})^{3}(\frac{2}{3}x^{-1}y)^{2}$
Evaluate the powers:
$(3xy^{2})^{3}(\frac{2}{3}x^{-1}y)^{2}=(27x^{3}y^{6})(\frac{4}{9}x^{-2}y^{2})=...$
Evaluate the product:
$...=(27)\Big(\dfrac{4}{9}\Big)x^{3-2}y^{6+2}=12xy^{8}$