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प्रश्न
Find the volume and the surface area of the spheres in the following :
Radius= 2.1 cm
उत्तर
Radius = 2.1 cm
Volume of sphere = `4/3pir^3`
= `4/3 xx 22/7 xx 2.1 xx 2.1 xx 2.1`
= 38.808 cm3
Surface area = `4pir^2`
= `4 xx 22/7 xx 2.1 xx 2.1`
= 55.44 cm2
Volume = 38.808 cm3 and Surface area = 55.44 cm2
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