Green house cost and volume

$r = 6\text{ m}$, $h = 2\text{ m}$. Surface Area = $2\pi r h + 2\pi r^2 = 2\pi r(h + r) = 2 \times \frac{22}{7} \times 6 \times 8 = \frac{2112}{7}\text{ m}^2$. Cost = $\frac{2112}{7} \times 70 = 21120$ rupees. Volume = $\pi r^2 h + \frac{2}{3}\pi r^3 = \frac{22}{7} \times 36 \times \left(2 + 4\right) = \frac{4752}{7} \approx 678.86\text{ m}^3$.