Question 1076358
radius of the platform=r
Area of the platform is pi*r^2
Area of the whole fountain is 2r
Area of the whole fountain is pi*4r^2
Area of the pool is pi*4r^2-pi*r^2=pi(3r^2)
This is a quadratic function.  Its area is the function of the square of the radius.
It helps to draw this.