int? num1 = 10;
int? num2 = null;
if (num1 >= num2)
{
    Console.WriteLine("num1 is greater than or equal to num2");
}
else
{
    Console.WriteLine("num1 >= num2 is false (but num1 < num2 also is false)");
}

if (num1 < num2)
{
    Console.WriteLine("num1 is less than num2");
}
else
{
    Console.WriteLine("num1 < num2 is false (but num1 >= num2 also is false)");
}

if (num1 != num2)
{
    Console.WriteLine("num1 != num2 is true!");
}

num1 = null;
if (num1 == num2)
{
    Console.WriteLine("num1 == num2 is true if the value of each is null");
}
// Output:
// num1 >= num2 is false (but num1 < num2 also is false)
// num1 < num2 is false (but num1 >= num2 also is false)
// num1 != num2 is true!
// num1 == num2 is true if the value of each is null