What is the formula for the circumference C of a circle of r

What is the formula for the circumference C of a circle of radius r? What is the formula for the area A of a circle of radius r? The formula for the circumference C of a circle of radius r is (Type an exact answer, using x as needed.)

The formulae for perimeter (circumference) and Area of the circle of radius is given by

Perimeter P=2r