Question

can anyone help me.

Answer 1

$Volume \: of \: earth \: = \pi {r}^{2} h \\ \\ \frac{22}{7} \times (\frac{14}{2})^{2} \times 20 \\ \\ \frac{22}{7} \times \frac{196}{4} \times 20 \\ \\ \frac{86240}{14} = {6160m}^{3}$
Now, Volume of platform
$= lbh = 6160 \\ 22 \times 14 \times h = 6160 \\ h = \frac{6160}{308} = 20m$