Shown below are six -7.0mC charges arranged a distance of 0.45m from a central point. All the charges are equally spaced around the point. [10 points] a. Calculate the total electric potential at the center of the charges. [6 pts] b. Imagine that the bottom charge (in yellow) was +7.0mC instead. What would the electric potential be at the center of the charges. [4 pts] If you changed three of the charges to be +7.0mC in the previous problem, the electric potential at the central point can become zero. Describe how those three positive charges would to be located around the shape in order to make V=0 at the center. Be sure to explain why those arrangements would make V=0. [5 points] X