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Find the surface area of a sphere of diameter 21 cm. (Use $π =\frac{22}{7}$) |
988 cm2 1234 cm2 1445 cm2 1386 cm2 |
1386 cm2 |
We have, The diameter of a sphere = 21 cm. Then the radius = \(\frac{21}{2}\) = 10.5 cm We know that, Surface area of a sphere = 4πr2 = 4 × \(\frac{22}{7}\) × (10.5 )2 = \(\frac{88}{7}\) × 110.25 = 1386 cm2 |
