1 using static System.Console; 2 class ShapesDemo 3 { static void Main() { abstract class GeometricFigure Create a Rectangle is a GeometricFigure 4 whose area is determined by multiplying width by height. 7 { 8 public int Height { 10 11 9. Create a Square is a get Rectangle in which the { 12 13 width and height are return height; the same. Provide a } 14 15 set constructor that accepts { 16 17 both height and height = value; width, forcing them to } be equal if they are not. 18 Provide a second 19 public int Width 20 { 21 22 constructor that accepts get just one dimension and { 23 24 uses it for both height return width; and width. The Square } 25 26 27 28 29 30 } 31 class uses the set Rectangle 's ComputeArea() method. width = value; Create a Triangle is a GeometricFigure whose area is determined 32 public int Area 33 { 34 by multiplying the width by half the height. get 35 { 36 return area; In the ShapesDemo 37 } class. after each object 38 } 39 is created, pass it to a method that accepts a 40 private void CalArea(). 41 { 42 43 } 44 GeometricFigure area = Height * Width; argument in which the figure's data is displayed. Change some dimensions 45 } 46 of some of the figures, and pass each to the display method again.