Answer
$a^{14}b^{11}$
Work Step by Step
Using $(ab)^x=a^xb^x$, then the expression, $
(a^4b^6)(a^2b)^5
$, simplifies to
\begin{array}{l}\require{cancel}
(a^4b^6)(a^{2(5)}b^5)
\\\\=
(a^4b^6)(a^{10}b^5)
.\end{array}
Using $a^x\cdot a^y=a^{x+y}$, then given expression, $
(a^4b^6)(a^{10}b^5)
$, simplifies to
\begin{array}{l}\require{cancel}
a^{4+10}b^{6+5}
\\\\=
a^{14}b^{11}
.\end{array}