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प्रश्न
Find the surface area of a sphere of radius 7 cm.
उत्तर
Given: Radius of the sphere, r = 7 cm
∴ Surface area of the sphere, S = `4pir^2`
`= 4 xx 22/7 xx (7)^2`
`= 4 xx 22/7 xx 49`
= 88 × 7
= 616 cm2
Thus, the surface area of sphere is 616 cm2.
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