The volume of a sphere is 38808 cu. cm. The curved surface area of the sphere (in cm²) is:

1. 1386

2. 4158

3. 5544

4. 8316

If the ratio of volumes of two spheres is 1 : 8, then the ratio of their surface areas is :

1. 1 : 2

2. 1 : 4

3. 1 : 8

4. 1 : 16

Volume of a cylinder of height 3 cm is 48π cm³. Radius of the cylinder is :

1. 48 cm

2. 16 cm

3. 4 cm

4. 24 cm

Three solid spherical beads of radii 3 cm, 4 cm and 5 cm are melted and recast into a single spherical bead. Its radius is :

1. 6 cm

2. 7 cm

3. 8 cm

4. 9 cm