Answer
$\text{Kind: }\text{
none of the choices given
}\\\text{Degree: }
4$
Work Step by Step
Since the +/- operator separates terms, the given polynomial expression, $
8s^3t-4s^2t^2+2st^3+9
,$ has $
4
$ terms.
The degree of a polynomial is the highest degree among all the terms. The term that has the highest degree is any of the first, second, or third terms given above.
Hence, the given polynomial has the following characteristics:
\begin{array}{l}\require{cancel}
\text{Kind: }\text{
none of the choices given
}\\\text{Degree: }
4
.\end{array}