Answer
$$ x=\sqrt[3] 2.$$
Work Step by Step
The zeros of $f(x)=2- x^3$ can be obtained by putting
$$2-x^3=0\Longrightarrow x=\sqrt[3] 2.$$
Since $f(-x)\neq -f(x)$ nor $f(-x)\neq f(x)$ then the function is not symmetric about the origin nor about the y-axis and it is decreasing on the interval $(-\infty,\infty)$. See the figure below.