Final answer:
Without the specified figure being present, there is not enough information to categorically identify members labeled AB as two-force or three-force members in a structural context. An analysis of force directions, magnitudes, and application points is necessary for accurate classification.
Step-by-step explanation:
To identify the two-force and three-force members in a given figure, particularly for the members labeled AB, we would generally consider if each member is subjected to forces at two points (two-force member) or more than two points (three-force member).
A two-force member is typically in pure tension or compression and will only have forces acting on either end of the member along its axis. In contrast, a three-force member has forces acting at three (or more) different points, which could be non-collinear and cause bending or other stresses in addition to tension or compression.
For the specific figure and members provided in the question, without the figure being present, we must state that there is not enough information to determine whether the members labeled AB are two-force or three-force members. To correctly make this determination, we would need to analyze the directions, magnitudes, and points of application of the forces acting on the member AB.