I'm fairly sure this is what the question is asking for ...
Parabola, Conic Sections
I'm taking an online class for Algebra II, and the first lesson concerns right circular cones and the curves resulting from intersecting planes; conic sections. Over half of the questions talk about the plane in relation to the "edge" of the cone. The first question is this:
If a right circular cone intersects a plane that runs parallel to the edge of the cone, the resulting curve will be a(n) ____.
I've combed through the section and checked its key terms. They are: circle, conic section, ellipse, hyperbola, nappe, parabola, right circular cone, vertex.
I know, or at least I think, an edge is the line where two faces meet. So I assumed it was where the base and the lateral surface (am I using that term correctly? I mean the part that wraps around the shape) met. That is, I thought being "parallel to the edge" would be the same as "parallel to the base", etc. And so because over half of the questions mention this "edge", I failed the quiz spectacularly. Luckily I can retake it. Once.
TLDR What is the edge of a cone!?