I have two problems that I need help working on. The first one is An electron is released from rest 2.0 cm from an infinite charged plane. It accelerates toward the plane and collides with a speed of 1.0 x 10^7 m/s. What is the surface charge density of the plane? The second problem is: A 75.7 nC charge is located at position (x,y) = (1.0 cm, 2.0 cm). At what (x,y) position(s) is the electric field: a) -225,000i N/C b) (161,000i + 85,000j) N/C and c) (21,600i - 28,800j) N/C.