For a system of tasks that may lock resources, the “wait-for” one of these constructs can be used to represent the system state and identify deadlocks. Weisfeiler-Leman algorithms are used on these objects, which may be used to construct a static schedule by building one of these objects. In 2015, László Babai announced work on a problem named for these objects that runs in quasipolynomial time. The expression D minus A gives a type of (*) Laplacian representing these objects. One of these objects (10[1])that obeys the triangle inequality is used as input for the Christofides algorithm. A minimum spanning tree (10[1])for these objects may be constructed with Kruskal’s algorithm. Causal diagrams (10[1])may use the “directed acyclic” form of, for 10 points, what objects that consist of a collection of vertices connected by edges? ■END■