Factor .
Factor completely:
$\left( r^{2}+ 3\right) \left(r^{2}+ 4\right)$
The polynomial is prime.
$\left( r^{3}+ 4\right) \left(r + 3\right)$
$\left( r^{3}+ 3\right) \left(r + 4\right)$
$\left( r^{2}+ 3\right) \left(r + 2\right)^{2}$
.
