static void Main(string[] args)
 {
     Console.WriteLine(Quater.GetFirstMonth(DateTime.Now.Month));
     Console.WriteLine(Quater.GetLastMonth(DateTime.Now.Month));
     Console.ReadLine();
 }
 static void Main(string[] args)
 {
     Console.WriteLine(Quater.GetFirstMonth(DateTime.Now.Month));    // Outputs october
     Console.WriteLine(Quater.GetLastMonth(DateTime.Now.Month));     // Outputs september
     Console.ReadLine();
 }