Part of a toy is made up of a block on top of another block. Both blocks are 6 cm by 8 cm. The top block rotates about its centre, X.
In the diagram above, A is the midpoint of a shorter side of the top block; B is a corner of the top block; and C is a point on the edge of both rectangles; and.
The points A, B and C all move on a circle as the top block rotates. What are the radii of these circles?