Determine the intervals of concavity and the inflection points of the function using the graph of $f^{\prime \prime }\left(x\right)$.

Inflection Points: $x=-3,3$

Concave up: $(-\infty ,-3)\cup (3,\infty )$

Concave down: $(-3,3)$

Inflection Points: $x=-3$

Concave up: $\left(-\infty,-3\right)\cup\left(3,\infty\right)$

Concave down: $\left(-3,3\right)$

Inflection Points: $x=-3,3$

Concave down: $\left(-\infty,-3\right)\cup\left(3,\infty\right)$

Concave up: $\left(-3,3\right)$

Inflection Points: $x=-5,0,5$

Concave up: $\left(-\infty,-3\right)\cup\left(3,\infty\right)$

Concave down: $\left(-3,3\right)$