Question

Question 2 (ii)
Find the surface area of a sphere of diameter:

(ii) 21 cm

$[Assume\pi =\frac{22}{7}]$

Answer 1

(ii) Radius (r) of the sphere $=\frac{21}{2}=10.5cm$

Surface area of the sphere $=4\pi r^2$

$=[4\times \frac{22}{7}\times (10.5{)}^2]c{m}^2=1386c{m}^2$