rake angle
A horizontal angle is an angle between lines on a horizontal plane.
Lines
They can be, but not necessarily. If two lines in the same plane never intersect, they are parallel. Though, two lines can exist in the same plane without being parallel. Ie, two lines that intersect at a 90 degree angle are perpendicular. Most lines in a plane aren't parallel.
If they are not parallel and do not intersect then they would not be in the same plane (not possible), but they would be called skew lines.
They are called skew lines.
It is because they are not in a plane that is parallel to the horizontal.
No. The angle of incidence will equal the angle of reflection. No convergence will take place.
In plane geometry, a shape with four sides, two of which are parallel and have the same length, cannot have a reflex angle.
A horizontal angle is an angle between lines on a horizontal plane.
Lines
They have the same angle relative to any plane or line and never intersect.
They can be, but not necessarily. If two lines in the same plane never intersect, they are parallel. Though, two lines can exist in the same plane without being parallel. Ie, two lines that intersect at a 90 degree angle are perpendicular. Most lines in a plane aren't parallel.
If they are not parallel and do not intersect then they would not be in the same plane (not possible), but they would be called skew lines.
Plane waves travel parallel to each other in the same plane hence the name.
They are called skew lines.
I'm assuming you are looking for the name of the conic section produced by this type of intersection? If a right circular cone is intersected by a plane parallel to one edge of the cone, the resulting curve of intersection would be a parabola. If the intersecting plane was parallel to the base, it would be a circle. If the intersecting plane was at any angle between being parallel to the base and being parallel to an edge, it would produce an ellipse or part of an ellipse (depending on whether the intersection was completely within the cone).
In a first angle projection, the object stands in between the observer and the plane of projection. In a third angle project, the object and the plane of projection is interchanged.