using System;

​

public class Program

{

    public static void Main()

    {

        double sm = 9;

        double sm1 = 9;

        double SmInch = 9 * 0.3937;  

        Console.WriteLine(SmInch);

        Console.WriteLine(" ");    

        double  inch = 9;

        double  Myas = inch * 2.54;

        Console.WriteLine(Myas);

        Console.WriteLine(" ");

​

        double a = 10;

        double b = 11;

        double s = (a + b) / 2;

        Console.WriteLine(s);

            }

        }

​