If the height of a cone is doubled, then its volume is increased by :

1. 100%

2. 200%

3. 300%

4. 400%

If the height of two cones are in the ratio of 1 : 4 and the radii of their bases are in the ratio 4 : 1, then the ratio of their volumes is:

1. 1 : 2

2. 2 : 3

3. 3 : 4

4. 4 : 1

The radii of the bases of a cylinder and a cone are in the ratio 3 : 4 and their heights are in the ratio 2 : 3. Then their volumes are in the ratio:

1. 3 : 4

2. 4 : 3

3. 8 : 9

4. 9 : 8

A right cylindrical vessel is full with water. How many cones having the same diameter and height as those of the right cylinder will be needed to store that water?

1. 2

2. 3

3. 4

4. 5