Four point charges are located at the corners of a square with each side of length (l) = 5.0 cm, as shown in the figure from the last problem. Charge q1 = q2 = +2.0 μC and charge q3 = q4 = +1.0 μC. Assume that a charge q5 = -2.0 μC is placed at point P. What is the force in unit vector notation on charge 5 due to other four charges?