$V_{cone} = \frac{1}{3}\pi(2^2)(6)$
$V_{cone} = 8\pi \, \text{ m}^3$
In upright position,
$\dfrac{V_{air}}{V_{cone}} = \dfrac{3^3}{6^3}$
$\dfrac{V_{air}}{8\pi} = \dfrac{27}{216}$
$V_{air} = \pi \, \text{ m}^3$
$V_{water} = V_{cone} - V_{air}$
$V_{water} = 8\pi - \pi$
$V_{water} = 7\pi \, \text{ m}^3$
$V_{water} = 21.991 \, \text{ m}^3$ Part 1: [ A ]
In inverted position:
$\dfrac{V_{water}}{V_{cone}} = \dfrac{h^3}{6^3}$
$\dfrac{7\pi}{8\pi} = \dfrac{h^3}{216}$
$h = 5.7388 \, \text{ m}$ Part 2: [ B ]
$\text{Weight of water} = \gamma_w V_{water} = 9800(21.991) = 215\,511.8 \, \text{ N}$
$\text{Weight of water} = 215\,511.8 \, \text{ N}\left( \dfrac{1 \, \text{ kg}}{9.81 \text{ N}} \right)\left( \dfrac{1 \, \text{ quintal}}{100 \text{ kg}} \right)$
$\text{Weight of water} = 219.686 \, \text{ quintals}$ Answer: [ C ]
