Answer the following questions for the function f(x)=x^3/x^2−16 defined on the interval [−20,18]

a.) Enter the xx-coordinates of the vertical asymptotes of f(x) as a comma-separated list.
b.) f(x) is concave up on the region:
c.) Enter the x-coordinates of the inflection point(s) for this function as a comma-separated list.