Answer:
[tex]radius \: of \: earth \: = 6.4 \times {10}^{6} \: m \\ volume \: of \: a \: sphere = \frac{4}{3} \pi {r}^{3} \\ = \frac{4}{3} \times 3.14 \times (6.4 \times {10}^{6} ) ^{3} \\ = 1.098 \times {10}^{21} \: {m}^{3} \\ or \\ = 1.098 \times {10}^{12} \: {km}^{3} [/tex]
