Write a method that takes two rectangles and returns the (positive) difference between their areas. This method must be named areaDiff() and have 2 Rectangle parameters. This method must return a double.

For example suppose two Rectangle objects were initialized as shown:

Rectangle rect1 = new Rectangle(2.0, 8.0);
Rectangle rect2 = new Rectangle(6.0, 3.0);
The method call areaDiff(rect1, rect2) should then return the value 2.0.