If you want to only calculate the extra potential energy that results from bringing up the test charge, q, how many PE terms do you have to calculate? Calculate the extra PEs for situations A,B, and C above. Take 1 unit distance to be d. Express your answers in the form U = kcqe/d by calculating the number in the brackets but don't bother to evaluate the number in front. Show briefly how you got your answers in the space below and put your answers in the box at the right.