I am supposed to write a code in Matlab that draws an Archimedes Spiral in circles as in the picture below.

I figured out how to draw the circles sprial and all but I am stuck in making them have different colors.

How can you specify multiple colors in the rectangle function and make the colors recycle around the spiral like in the photo?

Here's the code I wrote so far:

20 15 10 0 -5 -10 -15 -20 20 -10 0 10 20