Answer
$0.533\pi\, m^{3}/min$
Work Step by Step
$r=2\,m, h=3\,m$$\implies\frac{r}{h}=\frac{2}{3}\implies r=\frac{2}{3}h$
$V=\frac{1}{3}\pi r^{2}h=\frac{1}{3}\pi (\frac{2}{3}h)^{2}h=\frac{4\pi}{27}h^{3}$
$\frac{dV}{dt}=\frac{dV}{dh}\times\frac{dh}{dt}$$=\frac{4\pi}{27}\times3h^{2}\times\frac{dh}{dt}=\frac{12\pi}{27}\times h^{2}\times\frac{dh}{dt}$
When $\frac{dh}{dt}= 0.3\,m/min$ and $h=2\,m$,
$\frac{dV}{dt}= \frac{12\pi}{27}\times(2\,m)^{2}\times0.3\,m/min$
$\approx0.533\pi\,m^{3}/min$
