Question

The measuring line or the line of heights is the trace or the line of intersection with the _________ plane, of the vertical plane containing the point or points whose heights are to be determined.

(a) ground plane

(b) picture plane

(c) horizontal plane

(d) central plane

This question was addressed to me in quiz.

This intriguing question originated from Types of Perspective in section Oblique & Perspective Projection of Engineering Drawing

Answer 1

The correct answer is (b) picture plane

For explanation I would say: The measuring line or the line of heights is the trace or the line of intersection with the picture plane, of the vertical plane containing the point or points whose heights are to be determined. Heights of points lying in the different vertical plane can be measured from their respective line of heights.