Suppose that the polynomial function $f$ is defined as follows.

$f(x)=(x-5)(x+7)(x-9{)}^3$

List each zero of $f$ according to its multiplicity in the categories below.

If there is more than one answer for a multiplicity, separate them with commas. If there is no answer, click on "None."

$\{\begin{array}{ccc}\text{:}& \text{Z}\text{e}\text{r}\text{o}(s)of\text{m}\text{u}\text{l}\text{t}\text{i}\text{p}\text{l}\text{i}\text{c}\text{i}\text{t}\text{y}\text{o}\text{n}\text{e}\text{:}& \end{array}$