A charge of +3.5 µ C is placed on the x axis at x = +0.55 m, while a charge of –15 µ C is placed at the origin. (a) Calculate the magnitude and direction of the net electric field on the x axis at x = +0.8 m. (b) Determine the magnitude and direction of the force that would act on a charge of –8.0 µ C if it was placed on the x axis at x = +0.8 m.