Suppose that you are the experimenter of a project running several sections of both the experimental group and control group. The sections will be run on Thursday afternoon and Friday morning. The two rooms you have been assigned vary from each other: one has neutral paint on the walls; the other has bright orange psychedelic paint. How can physical effects be minimized as potential confounding influences in this study? Then suppose that you have another experimenter with the same scenario helping you run some of the sections. She frequently dresses in "Goth" makeup and outfits. What steps can be taken to minimize confounding caused from personality variables