A solid piece of iron in the form of a cuboid of dimensions 49 cm × 33 cm × 24 cm is molded to form a sphere. The radius of the sphere is

1. 21 cm

2. 23 cm

3. 25 cm

4. 19 cm

If a solid circular cylinder of iron whose diameter is 15 cm and height 10 cm is melted and recasted into a sphere, then the radius of the sphere is

1. 15 cm

2. 10 cm

3. 7.5 cm

4. 5 cm

The number of balls of radius 1 cm that can be made from a sphere of radius 10 cm is

1. 100

2. 1000

3. 10000

4. 100000