A hemispherical bowl made of brass has inner radius 10.5 cm. Find the cost of polishing it on the inside at the rate of र 0.12 per sq. cm.
Solution not provided.
Ans. 0.77 m3
A hollow right circular cylindrical copper pipe is 21 cm long. Its outer and inner diameters are 10 cm and 6 cm respectively. Find the volume of copper used in making the pipe.
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