A circus tent is made of canvas and is in the form of right circular cylinder and a right circular cone above it. The diameter and height of cylindrical part of tent are 126 m and 5 m respectively. The total height of the tent is 21 m. Find the total cost of tent if canvas used costs ₹36 per square metre.

The entire surface of a solid cone of base radius 3 cm and height 4 cm is equal to entire surface of a solid right circular cylinder of diameter 4 cm. Find the ratio of their

(i) curved surfaces

(ii) volumes.

A hemisphere of lead of radius 8 cm is cast into a right circular cone of base radius 6 cm. Determine the height of the cone correct to 2 places of decimal.

Find the least number of coins of diameter 2.5 cm and height 3 mm which are to be melted to form a solid cylinder of radius 3 cm and height 5 cm.