the question that needs to be answered is question 2

This passage and figure relate to problems 1-3: The electrical characteristics of human skin are modulated, in part, by the activity of the sympathetic nervous system. These electrical properties have been used as an indicator of physiological arousal and even as an indirect measure of the health of the living epidermis layer. The diagram below depicts a set of equipotential lines measured on the surface of the skin. The following 3 questions ask you to interpret certain features of this diagram. Please note that the scale bar in the lower left of the figure represents a length of 1cm. +30 mV +20/mV +10/mV 0 mV -10 mV +40 mV -20 mV