4) Name the curve of intersection of a vertical cone cut by an auxiliary vertical plane.

5) When a vertical cylinder is penetrated by a horizontal cylinder, the top view of the intersection is?

6) When two prisms are intersected at right angle, the intersection is made up of?

7) When a cylinder penetrates into a vertical cone with their axes parallel to each other, the top view of the intersection is?

8) The line of intersection between cylinder an cone, unless they envelop a common sphere is made up of?