The number of solid spheres, each of diameter 6 cm that can be moulded to form a solid metal cylinder of height 45 cm and diameter 4 cm, is :

1. 3

2. 4

3. 5

4. 6

If the height and diameter of a right circular cylinder are 32 cm and 6 cm respectively, then the radius of the sphere whose volume is equal to the volume of the cylinder is :

1. 3 cm

2. 4 cm

3. 4.5 cm

4. 6 cm

If a sphere just fits in a right circular cylinder, then the ratio of the volume of sphere to the volume of the cylinder is :

1. 1 : 3

2. 1 : 2

3. 2 : 3

4. 1 : 4

A sphere of radius 6 cm is dropped into a cylindrical vessel, partly filled with water. The radius of the vessel is 8 cm. If the sphere is submerged completely, then the surface of the water rises by :

1. 2 cm

2. 3 cm

3. 4 cm

4. 4.5 cm