Question

consider the diagram. lines a and d are non - coplanar. parallel. perpendicular. skew.

Explanation:

Step1: Recall definitions

• Non - coplanar: Lines that do not lie on the same plane. But in 3 - D space, we need to check other properties.
• Parallel: Lines that are in the same plane and never intersect.
• Perpendicular: Lines that intersect at a right - angle (90 degrees).
• Skew: Non - parallel, non - intersecting, and non - coplanar lines.

Step2: Analyze the lines

• Lines \(a\) and \(d\) are not parallel (their directions are different).
• They do not intersect (as per the diagram's 3 - D nature).
• They are not coplanar (since one is in a vertical - like plane and the other is in a horizontal - like plane in the 3 - D structure).

Answer:

skew.