Two charges are placed on the x axis. One of the charges (q1 = +5.44C) is at x1 = +3.00 cm and the other (q2 = -27.7C) is at x2 = +9.00 cm. Find the net electric field (magnitude and direction given as a plus or minus sign) at (a) x = 0 cm and (b) x = +6.00 cm.