Analyze the function $p\left(x\right)=(x+1)(x-6{)}^2$ to determine the intervals of concavity.

Concave up on $(-\infty ,\frac{11}{3})$

Concave down on $(\frac{11}{3},\infty )$

Concave up on $(\frac{11}{3},\infty )$

Concave down on $(-\infty ,\frac{11}{3})$

Concave up on $(-\infty ,11)$

Concave down on $(11,\infty )$

Concave up on $(11,\infty )$

Concave down on $(-\infty ,11)$