An electron with a speed 5.00x10^8 cm/s enters an electric field of magnitude 1.00x10^3 N/C, traveling along a field line in the direction that retards its motion. (a) how far will the electron travel in the field before stopping momentarily, and (b) how much time will have elapsed? (c) If the region containing the electric field is .08m long, what fraction of the electron's initial kinetic energy will be lost in that region?