Working with circle and ellipse - 2

Here you can see the formula of a circle. It has the center (0/0) and the radius 2 (the square root of 4).
1.) Use the input boxes to create the same circle again. Your formula is (x-m)^2 + (y-n)^2 = r. 2.) Use the input boxes again and create a circle with center (2/3) and radius 4. If you need help use the Hint button.