a. Given that the distance d in the figure is 4.11 cm , find the magnitude of the net electrostatic force exerted on the point charge q1 .
b.Find the direction of the net electrostatic force exerted on the point charge q1 in Part A.
Data: The point charges in the figure below have the following values: q1 = 2.0 ?C, q2 = 6.0 ?C, q3 = -0.87 ?C .