We prove that there does not exist a subset of the plane S that meets every isometric copy of the vertices of the unit square in exactly one point. We give a complete characterization of all three point subsets F of the reals such that there does not exists a set of reals S which meets every isometric copy of F in exactly one point.

Maslach and Jackson first introduced the concept of ‘burnout’- a state of physical and emotional exhaus- tion emerging from work conditions- in 1980. The importance of investigations of burn out lies in the fact that it is directly related to the quality of teaching. There are three basic criteria set to predict, evaluate, and prevent burnout: depersonalization, emotional exhaustion, and person...