using System;

using System.Threading.Tasks;

using System.Net.Http;

using System.Linq;

public class Program

{

    static void Main(string[] args)

    {

        var client = new HttpClient();

        var tasks = new List<Task>();

​

        for (var i = 0; i < 10; i++)

        {

            tasks.Add(SendRequest(client, "http://slowwly.robertomurray.co.uk/delay/5000/url/https://habr.com"));

        }

​

        Task.WaitAll(tasks.ToArray());

    }

​

    private static async Task SendRequest(HttpClient client, string url)

    {

        var response = await client.GetAsync(url);

        Console.WriteLine($"Received response {response.StatusCode} from {url}");

    }

}