**Q: **Is a cone a three-dimensional geometric shape that tapers smoothly from a flat base to a point called the apex or vertex? ¶

**A: **Yes.

**Q: **Is a cone right circular the intersection of a plane with the lateral surface is a conic section? ¶

**A: **Yes.

**Q: **Is a cone called the "directrix"? ¶

**A: **Yes, and each of the line segments between the directrix and apex is a "generatrix" or "generating line" of the lateral surface.

**Q: **Are cones not usually special? ¶

**A: **Yes, in fact one is often interested in polyhedral cones.

**Q: **Is a cone the radius of its base? ¶

**A: **Yes, often this is simply called the radius of the cone.

**Q: **Is a cone the straight line? ¶

**A: **Yes, and passing through the apex, about which the base has a circular symmetry.

**Q: **Are cones oblique cones? ¶

**A: **Yes, and in which the axis passes through the centre of the base non-perpendicularly.

**Q: **Are cones assumed to be right circular? ¶

**A: **Yes, where circular means that the base is a circle and right means that the axis passes through the centre of the base at right angles to its plane.

**Q: **Is a cone the distance from any point on the circle to the apex of the cone via a straight line along the surface of the cone? ¶

**A: **Yes.

**Q: **Is a cone a conic section? ¶

**A: **Yes.

**Q: **Is a cone formed by a set of line segments? ¶

**A: **Yes, and half-lines, or lines connecting a common point, the apex, to all of the points on a base that is in a plane that does not contain the apex.

**Q: **Is a cone a solid object? ¶

**A: **Yes, otherwise it is a two-dimensional object in three-dimensional space.