A spherical chocolate ball has a layer of ice-cream of uniform thickness around it. When the thickness of the ice-cream layer is 1 cm , the ice-cream melts at the rate of 81 cm3/min and the thickness of the ice-cream layer decreases at the rate of 4π1 cm/min. The surface area (in cm2 ) of the chocolate ball (without the ice-cream layer) is :
Held on 23 Jan 2025 · Verified 6 Jul 2026.
196π
256π
225π
128π
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