If the radii of two cylinders are in the ratio 4 : 3 and their heights are in the ratio 5 : 6, find the ratio of their curved surfaces.

A thin rectangular card board has dimensions 44 cm x 22 cm. It is rolled along its length to get a hollow cylinder of largest size. Find the volume of the cylinder formed.

If radii of two circular cylinders are in the ratio 3 : 4 and their heights are in the ratio 6 : 5, find the ratio of their curved surface areas.

The lateral surface area of a cube is 100 cm²; then its volume is :

1. 25 cm³

2. 125 cm³

3. 625 cm³

4. none of these