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A sphere has diameter 21 cm. Its surface area (take π = 22/7) is:

Class 9Surface Area of a SphereMensuration

A $1386 cm^{2}$
B $693 cm^{2}$
C $5544 cm^{2}$
D $346.5 cm^{2}$

Step-by-Step Solution

Radius =

\frac{21}{2} = 10.5

cm. 4*π*

r^{2} = 4 * (22/7) * 10.5 \times 10.5 = 4 * (22/7) * 110.25 = 1386 cm^{2}

.

Answer: A)

1386 cm^{2}

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