static void Main(string[] args) { GSM phone = new GSM("lala", "sumsAng", "batman", 10000.99); phone.MakeCall(DateTime.Now, "0899999999", 3.44); phone.MakeCall(DateTime.Now.AddHours(3), "0899999999", 3.44); phone.MakeCall(DateTime.Now.AddDays(99), "0889666999", 9.44); phone.MakeCall(DateTime.Now.AddDays(5).AddHours(10), "0009666999", 9.44); Console.Write(phone.ToString()); phone.setCallRate = 0.37; Console.WriteLine("{0:F2}", phone.CalculateTotalPriceOfCalls()); }