Question

Find The Surface area of a Sphere of Radius 4.2?

Answer 1

$Surface \: area \: of \: a \: Sphere = 4 \pi \: {r}^{3} \\ \\ = 4 \times \frac{22}{7} \times \frac{42}{10} \times \frac{42}{10} \times \frac{42}{10} \\ \\ = \frac{4 \times 22 \times 6 \times 42 \times 42}{1000} \\ \\ = \frac{931,392}{1000} \\ \\ = 931.392$