Operators - General Questions

What is the output of the following program?

object o = "hi";
if (o is string s) Console.WriteLine(s.Length);

What is the output of the following program?

int x = 5;
int y = x++ + ++x;
Console.WriteLine($"{x} {y}");

What is the output of the following program?

bool f = false;
Console.WriteLine(!f && (3 > 2));

What is the output of the following program?

int x = 7;
Console.WriteLine(x > 5 ? "big" : "small");