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Question
Find the surface area of a sphere of radius 5.6 cm.
`["Assume "pi=22/7]`
Solution
Radius(r) of sphere = 5.6 cm
Surface area of sphere = 4πr2
`=[4xx22/7xx(5.6)^2]cm^2`
= (88 × 0.8 × 5.6) cm2
= 394.24 cm2
Therefore, the surface area of a sphere having radius 5.6 cm is 394.24 cm2.
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(use π = `22/7`)