// overloaded constructor
 public Employee(string name, string lastName, string postion, double salary, Department department, Benefit benefit)
 {
     this.FirstName = name;
     this.LastName = lastName;
     this.Postion = postion;
     this.AnnualSalary = salary;
     this.department = department;
     this.benefit = benefit;
 }
 // default constructor
 public Employee()
 {
     department = new Department();
     benefit = new Benefit();
 }
 public Salaried(string name, string lastName, string postion, double salary, Department department, Benefit benefit)
     : base(name, lastName, postion, salary, department,benefit)
 {
 }