How far away would Proxima Centauri be from the Sun?

The diameter of the Sun is 1.4 multiplied by 1011 cm, and the distance to the nearest star, Proxima Centauri, is 4.2 ly. Suppose you want to build an exact scale model of the Sun and Proxima Centauri, and you are using a basketball 20 cm in diameter to represent the Sun. In your scale model, how far away would Proxima Centauri be from the Sun?