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Question 2:
Find the surface area of a sphere of diameter:
(i) 14 cm (ii) 21 cm (iii) 3.5 m
(i) Radius (r) of sphere = 
Surface area of sphere = 4πr2
Therefore, the surface area of a sphere having diameter 14 cm is 616 cm2.
(ii) Radius (r) of sphere =
Surface area of sphere = 4πr2
Therefore, the surface area of a sphere having diameter 21 cm is 1386 cm2.
(iii) Radius (r) of sphere = 
m
Surface area of sphere = 4πr2
Therefore, the surface area of the sphere having diameter 3.5 m is 38.5 m2.
