Volume of a sphere = 4/3Β ΟrΒ³
Volume of a sphere with radius 10 inches = 4/3Ο(10)Β³ inΒ³
Volume of a sphere with radius 20 inches = 4/3Ο(20)Β³ inΒ³
Volume added = 4/3Ο(20)Β³ - 4/3Ο(10)Β³ = 29321.5 inΒ³ (nearest tenth)
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Answer: Volume = 2932`.5 inΒ³ (Answer C)
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