e. Think of the right circular cone as being enclosed within a
cylinder, both having the same base and the same axis.
Figure 2-11 shows
the cone first on its side, then resting on its sloping side. Notice that
the long diameter of the ellipse representing the cone's circular base has
been drawn at right angles to the cone's axis, a relationship that is
constant in the cone as it is with the cylinder. Figure 2-11 shows several
examples of circular construction based on the shape of the cone.