In the x-y plane, a charge of -4.6 uC is on the x-axis at the point (-30cm,0) and a second charge of +7.2 uC is located on the y-axis at the point (0, 40cm) a) caclulate the magnitude and direction of the resultant electric field E at the origin (0cm,0cm) b) Calculate the magnitude and direction of the electric force F {using F=qE} acting on an ion of charge -3e if this particle were placed at the origin: