The coefficient of $x y^{2} z^{3}$ in the expansion of $(x-2 y+3 z)^{3}$ is

The set of all real values of $x$ for which the expansion of $\left(125 x^{2}-\frac{27}{x}\right)^{\frac{-2}{3}}$ is valid, is

If $3^{2 n+2}-8 n-9$ is divisible by $2^{p}, \forall n \in \mathrm{~N}$, then the maximum value of $P$ is

If the coefficient fo $x^{r}$ in the expansion of $\left(1+x+x^{2}+x^{3}\right)^{100}$ is $a_{r}$ and $S=\sum_{r=0}^{300} a_{r}$ then $\sum_{r=0}^{300} r \cdot a_{r}=$