A toy is made in the shape of a hemisphere of diameter 7 cm surmounted by a cone. If this 15.5 cm high toy is polished at 20 paise per cm$^2$, then find the cost of polishing. Take $\pi = \frac{22}{7}$

From a solid cylinder whose height is 2.4 cm and diameter is 1.4 cm, a conical cavity of same height and same diameter is carved out. The total surface area of the remaining solid is:

Use $\pi = \frac{22}{7}$

A metallic sphere of radius 6 cm is melted and recast into a cone of radius 4 cm. Find the height of the cone.

The solid and the Surface area (S.A) of the following solids are given below.

(A) A cube of edge 9 cm., S.A = $486 \text{ cm}^2$

(B) A cuboid of 18 cm. long, 14 cm. width and 7 cm. height, S.A = $108 \text{ cm}^2$

(C) A cylinder with diameter of 14 cm. and height 80 cm., S.A = $3520 \text{ cm}^2$

(D) A sphere with radius of 14 cm., S.A = $2004 \text{ cm}^2$

Choose the correct answer from the options given below:

The ratio of the diameter and height of the right circular cylinder is 4 : 3. If the diameter of the cylinder is reduced 25 %, then its total surface area is reduced to 318.5π m². What is the circumference of the base of the cylinder?

If a metallic rod of 10 cm length and 2 cm radius is stretched into a wire of 40 m length having uniform thickness, then find the radius of the stretched wire.

The areas of three adjacent faces of a cuboidal box are 96 cm², 48 cm² and 72 cm², respectively. The volume of the box is