Write the ratio of total surface area to the curved surface area of a cylinder of radius r and height h.

A well with 10 m inside diameter is dug 8.4 m deep. Earth taken out of it is spread all around it to a width of 7.5 m to form an ambankment. Find the height of the embankment.

Write the number of surfaces of a right curcular cylinder.

The ratio between the radius of the base and height of a cylinder is 2 : 3. If its volume is 1617 cm³, find the total surface area of the cylinder.

If the radii of two cylinders are in the ratio 2 : 3 and their heights are in the ratio 5 : 3, then find the ratio of their volumes.