1) Two point charges lie on the axis. A charge of 6.4 uC is at the origin, and a charge of -9.5 uC is at x = 10cm . What is the net electric field at (a) c = -4.0 cm and at (b) x = +4.0cm ? 2) The figure shows a system consisting of three charges q1 = +5.00 uC, q2 = +5.00 uC, q3 = -5.00 uC, and at the vertices of an equilateral triangle of side d = 2.85 cm. Find the magnitude of the electric field at a point halfway between the charges q1 and q2 .