
$\mathrm{V}=2500 \mathrm{cc}$
$\mathrm{h}=\frac{2500}{50 \times 5}=10 \mathrm{~cm}$
$\mathrm{C}_{\mathrm{d}}=\frac{\mathrm{A}_{\mathrm{d}} \varepsilon_0 \mathrm{k}}{\mathrm{d}}$
$=\frac{50 \times 10^{-2} \times 10 \times 10^{-2} \varepsilon_0 \times 3}{5 \times 10^{-2}}=3 \varepsilon_0$
$\mathrm{C}_{\mathrm{a}}=\frac{\mathrm{A}_{\mathrm{a}} \varepsilon_0}{\mathrm{~d}}=\frac{50 \times 10^{-2} \times 40 \times 10^{-2} \varepsilon_0}{5 \times 10^{-2}}=4 \varepsilon_0$
$\mathrm{C}=\mathrm{C}_{\mathrm{a}}+\mathrm{C}_{\mathrm{d}}=7 \varepsilon_0$
$=7 \times 9 \times 10^{-12}=63 \mathrm{Pf}$


(Take density of water $=1 \mathrm{~g} / \mathrm{cc}$ )

