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Question
Find the total surface area of a hemisphere of radius 10 cm. [Use π = 3.14]
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Solution

Radius (r) of hemisphere = 10 cm
Total surface area of hemisphere = Curved surface area of a hemisphere + Area of circular end of hemisphere
= 2πr2 + πr2
= 3πr2
= [3 × 3.14 × (10)2] cm2
= 942 cm2
Therefore, the total surface area of such a hemisphere is 942 cm2.
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