Find the surface area of a sphere of diameter: (i) $14$ cm

Find the radius of a sphere whose surface area is $154$ cm$^2$.

Find the surface area of a sphere of radius: (iii) $14$ cm

Find the surface area of a sphere of radius: (i) $10.5$ cm

A right circular cylinder just encloses a sphere of radius $r$ (see Fig. 11.10). Find (iii) ratio of the areas obtained in (i) and (ii).

Find the surface area of a sphere of diameter: (ii) $21$ cm

Find the surface area of a sphere of diameter: (iii) $3.5$ m

Find the surface area of a sphere of radius: (ii) $5.6$ cm

The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas.

The radius of a spherical balloon increases from $7$ cm to $14$ cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases.

A right circular cylinder just encloses a sphere of radius $r$ (see Fig. 11.10). Find (i) surface area of the sphere,

Find the total surface area of a hemisphere of radius $10$ cm. (Use $\pi = 3.14$)

A right circular cylinder just encloses a sphere of radius $r$ (see Fig. 11.10). Find (ii) curved surface area of the cylinder,

A hemispherical bowl is made of steel, $0.25$ cm thick. The inner radius of the bowl is $5$ cm. Find the outer curved surface area of the bowl.

A hemispherical bowl made of brass has inner diameter $10.5$ cm. Find the cost of tin-plating it on the inside at the rate of ₹ $16$ per $100$ cm$^2$.