13) What is the area of an ellipse if the major and minor axes are 5 cm and 3 cm respectively?

14) Find the total surface area of cube whose side is 25 cm.

15) Find the total surface area of a cast iron bar whose length, width and height are 20m, 15m and 12m.

16) What is the formula for total surface area of a cylinder?

17) What is the volume of a rectangular tank of 30 m length, 20m width and 10m height?