(Payroll System Modification) Modify the payroll system of Figs. 20.9–20.17 to includeprivate data member birthDate in class Employee. Use class Date from Figs. 18.6–18.7 to representan employee’s birthday. Assume that payroll is processed once per month. Create a vector of Employee references to store the various employee objects. In a loop, calculate the payroll for each Employee (polymorphically), and add a $100.00 bonus to the person’s payroll amount if the currentmonth is the month in which the Employee’s birthday occurs.

(Package Inheritance Hierarchy) Use the Package inheritance hierarchy created inExercise 19.9 to create a program that displays the address information and calculates the shippingcosts for several Packages. The program should contain a vector of Package pointers to objects ofclasses TwoDayPackage and OvernightPackage. Loop through the vector to process the Packagespolymorphically. For each Package, invoke get functions to obtain the address information of thesender and the recipient, then print the two addresses as they would appear on mailing labels. Also,call each Package’s calculateCost member function and print the result. Keep track of the totalshipping cost for all Packages in the vector, and display this total when the loop terminates.

4. Explain dangling and void pointer with example.

(Modifying Class GradeBook) Modify class GradeBook (Figs. 16.11–16.12) as follows:a) Include a second string data member that represents the course instructor’s name.b) Provide a set function to change the instructor’s name and a get function to retrieve it.c) Modify the constructor to specify course name and instructor name parameters.d) Modify function displayMessage to output the welcome message and course name,then the string "This course is presented by: " followed by the instructor’s name.Use your modified class in a test program that demonstrates the class’s new capabilities.

(Dynamic Binding vs. Static Binding) Distinguish between static binding and dynamicbinding. Explain the use of virtual functions and the vtable in dynamic binding

(Richer Shape Hierarchy) The world of shapes is much richer than the shapes included inthe inheritance hierarchy of Fig. 19.3. Write down all the shapes you can think of—both two-dimensional and three-dimensional—and form them into a more complete Shape hierarchy with asmany levels as possible. Your hierarchy should have the base class Shape from which class TwoDimensionalShape and class ThreeDimensionalShape are derived. [Note: You do not need to write any codefor this exercise.] We’ll use this hierarchy in the exercises of Chapter 20 to process a set of distinctshapes as objects of base-class Shape. (This technique, called polymorphism, is the subject ofChapter 20.)

State if true or false: Dynamic binding with virtual functions occurs only with pointers and references

4A in Python language please:

USE PYTHON PROGRAMMING LANGUAGE(OOP) 1. (Geometry: n-sided regular polygon) An n-sided regular polygon’s sides all have the same length and all of its angles have the same degree (i.e., the polygon is both equilateral and equiangular). Design a class named RegularPolygon that contains: ■ A private int data field named n that defines the number of sides in the polygon. ■ A private float data field named the side that stores the length of the side. ■ A private float data field named x that defines the x-coordinate of the center of the polygon with a default value 0. ■ A private float data field named y that defines the y-coordinate of the center of the polygon with a default value 0. ■ A constructor that creates a regular polygon with the specified n (default 3), side (default 1), x (default 0), and y (default 0). ■ The accessor and mutator methods for all data fields. ■ The method getPerimeter() returns the perimeter of the polygon. ■ The method getArea() returns the area of the…