public static int CalculateResult()
        {
            Console.WriteLine("Work Starting");
            Thread.Sleep(2000);
            Console.WriteLine("Work Finished");
            return 99;
        }
        public static void ReturnValue()
        {
            //creating task with return value
            Task<int> task = Task.Run(() =>
            {
                return CalculateResult();
            });
            //program waits when result property is read
            Console.WriteLine(task.Result);
            Console.WriteLine("Finished Processing. Press a key to end");
            Console.ReadKey();
        }