WEBVTT

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Here is the problem: Find the volume and surface area of a hemisphere with radius 4.

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Compute the volume (cubic units) and total surface area (square units) of the solid from its dimensions in one length unit.

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Volume: half a sphere.

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Surface area: curved half plus the flat disc.

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So the answer is Volume equals 128pi/3 approximately 134.0412866 cubic units; surface area equals 48pi approximately 150.7964474 square units.

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Volume counts unit cubes inside a solid; surface area counts unit squares needed to wrap it. Doubling every length multiplies volume by 8 and surface area by 4.

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Volume 134.0412866 and surface area 150.7964474 are positive.