  We show how to edge-unfold a new class of convex polyhedra, specifically a
new class of prismatoids (the convex hull of two parallel convex polygons,
called the top and base), by constructing a nonoverlapping "petal unfolding" in
two new cases: (1) when the top and base are sufficiently far from each other;
and (2) when the base is a rectangle and all other faces are nonobtuse
triangles. The latter result extends a previous result by O'Rourke that the
petal unfolding of a prismatoid avoids overlap when the base is a triangle
(possibly obtuse) and all other faces are nonobtuse triangles. We also
illustrate the difficulty of extending this result to a general quadrilateral
base by giving a counterexample to our technique.
