Two charges are placed on the x axis. One of the charges (+7.5 uC) is at x = +4.0 cm, and the other (-1.8 UC) is at x = +8.0 cm. Find the net electric field (magnitude and direction) at x = +1.0 cm. 7.2 x 10^7 N/C to the right 7.2 x 10^7 N/C to the left 4.2 x 10^7 N/C to the right 7.5 x 10^7 N/C to the right 4.2 x 10^7 N/C to the left 7.5 x 10^7 N/C to the left