Let $f\left(n\right)=\sum _{r=0}^n\left(\sum _{k=r}^n\left(\begin{array}{c}k\\ r\end{array}\right)\right).$ Then, the total number of divisors of $f\left(9\right)$ is

Let $X=\left\{1, 2, 3, 4, 5\right\}.$ The number of different ordered pair $\left(Y, Z\right)$ that can be formed such $Y\subseteq X, Z\subseteq X$ and $Y\cap Z$ is empty, is