Open the VB2015\Chap11\Formula Solution\Formula Solution (Formula Solution.sln) file. Open the Areas.vb file, which contains the Parallelogram class definition. The class contains two Public properties and two constructors. It also contains a GetArea method that calculates the area of a parallelogram.

a. Create a derived class named Triangle. The derived class should inherit the properties and GetArea method from the Parallelogram class. However, the Triangle class’s GetArea method should calculate the area of a triangle. The formula for calculating the area of a triangle is base * height / 2. Be sure to include a default constructor and a parameterized constructor in the derived class.

b. The btnCalc_Click procedure should display either the area of a parallelogram or the area of a triangle. The appropriate area to display depends on the radio button selected in the interface. Code the button’s Click event procedure, and then test the application appropriately.