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If the radius of a sphere is doubled, its surface area becomes:

Class 9Surface Area of a SphereMensuration

A4 times
B2 times
C8 times
D3 times

Step-by-Step Solution

Surface area = 4*π*

r^{2}

is proportional to

r^{2}

. Doubling

r

multiplies area by

2^{2} = 4

.

Answer: A) 4 times

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