At right is a photo of a tree trunk. Sketch (or trace) the outline of the visible portion shown here. Indicate where slices should be made so that the cross-section is:

1. One circular region (the region might not be a perfect circle, but it should be close).

2. Three separate circular regions.

3. A free form, amoeba-type shape.

   Hint (a - c):

   Look at the different points on the tree that are connected to the question.