public static void Main()
double c, d, sum, subtraction, product, division;
Console.WriteLine("The sum of " + a + " and " + b + " is: " + sum);
Console.WriteLine(d + " minus " + b + " is: " + subtraction);
Console.WriteLine("The product of " + b + " and " + c + " is: " + product);
Console.WriteLine("The division of " + d + " and " + b + " is: " + division);