If the radius of the base of a right circular cylinder is halved, keeping the height same, what is the ratio of the volume of the new cylinder to that of the original one?

1. 1 : 2

2. 1 : 4

3. 1 : 8

4. 4 : 1

The curved surface area of a cylinder is 4400 cm² and the circumference of its base is 110 cm. The volume of the cylinder (in cm³) is :

1. 36000

2. 38500

3. 40150

4. 42250

Two rectangular sheets of paper each 30 cm × 18 cm are made into two right circular cylinders, one by rolling the paper along its length and the other along the breadth. The ratio of the volumes of the two cylinders, thus formed, is :

1. 2 : 1

2. 3 : 2

3. 4 : 3

4. 5 : 3

Two cylindrical vessels with radii 15 cm and 10 cm and heights 35 cm and 15 cm respectively are filled with water. If this water when poured into a cylindrical vessel, 15 cm in height, fills it completely then the radius of the vessel is :

1. 17.5 cm

2. 18 cm

3. 20 cm

4. 25 cm