The potential in a region between x = 0 and x = 10.0 m is V = b + mx, where b = 20.0 V and m = -6.00 V/m. Find (a) the potential at x = 0, 2.00 m and 5 m and (b) determine the magnitude and direction of the electric field at x = 0, 2.00 m and 5.00 m.