Answer
a.$\quad p(x)=(x-1)\sqrt{x+10}$
b.$\quad [-10,0)$
c.$\quad-14$
Work Step by Step
$a.$
$p=fg$ is the function specified by $p(x)=f(x)g(x)$.
$p(x)=(x-1)\sqrt{x+10}$
$b.$
See "Note on Domains" p.70-71
Domain of $f+g, f-g$, and $fg$:
All real numbers $x$ simultaneously in the domains of f and $g$
Here, the domain of u is contained in the domain of g, so
Domain: $[-10,0)$
$c.$
$p(-6)=(-6-1)\sqrt{-6+10}=(-7)\sqrt{4}=-7(2)=-14$
