5.1-µC point charge is located at x = 1.1 m, y = 2.8 m, and a -3.9-µC point charge is located at x = 2.3 m, y = -1.9 m. (a) Find the magnitude and direction of the electric field at x = -2.9 m, y = 1.1 m.
(b) Find the magnitude and direction of the force on a proton at x = -2.9 m, y = 1.1 m.