Object Oriented review - Abstract, inherent, Virtual
Abstract class: using System; namespace App { public abstract class Saleman { private string _firstname; private string _lastname; public string Fullname { get { return string.Format("{0} {1}", this._firstname, this._lastname); } } public Saleman(string firstname, string lastname) { this._firstname = firstname; this._lastname = lastname; } public abstract void Sell(); } } ---------------------------------- using System; namespace App { public class CarSalePerson : Saleman { public CarSalePerson(string firstname, ...