By definition, a secondary auxiliary view is generated by projecting from a primary auxiliary view (not directly from a principal view). Assess whether this definition is correct.

Introduction / Context:
Auxiliary views reveal the true shape/size of features that are inclined to the principal planes. Sometimes a single rotation is insufficient; a second rotation around a new reference line is needed. The resulting view is called a secondary auxiliary view. We test the statement that it is projected from the first (primary) auxiliary view.

Given Data / Assumptions:

• Primary auxiliary: constructed from a principal view using a first reference line.
• Secondary auxiliary: constructed from the primary auxiliary using a second reference line.
• Objective: obtain true size/length for edges/planes still foreshortened after the first rotation.

Concept / Approach:
If a feature is oblique (inclined to two principal planes), the primary auxiliary removes foreshortening in one direction only. The secondary auxiliary then removes the remaining foreshortening by projecting again, but now from the already-rotated geometry in the primary auxiliary view.

Step-by-Step Solution:
1) Build the primary auxiliary from the chosen principal view.2) Identify edges/planes still not in true size.3) Establish a second reference line on the primary auxiliary.4) Project perpendicularly from the primary auxiliary to construct the secondary auxiliary.

Verification / Alternative check:
Checking true-length edges on the secondary auxiliary confirms that the second projection acted on the already-rotated geometry, not the original principal view.

Why Other Options Are Wrong:
“Incorrect”: Misstates the definition.“Projected from top only” / “Mirrored front” : Secondary auxiliaries depend on geometry, not a fixed principal view or mirroring.

Common Pitfalls:
Accidentally projecting the secondary directly from a principal view; misplacing the second reference line leading to distortion.

Final Answer:
Correct