need fast help

An infinite plane of charge with o = 65.0 nC/m lies in the xy plane. Recall that the electric field due to a non-conducting plane of charge in the ry plane may be expressed as E = = = k. a) Using the given equation for the electric field, determine the general expression for the potential difference between two values of z, where z > 0. Express your answer in terms of arbitrary initial and final points z; and zf. b) Using your answer from part a, determine the potential difference between z; = 5.80 m and zf = 0.35 m. c) A proton is moving towards the plane. If its initial velocity is v; = -3.05 x 105k m/s at z = 5.80 m, what will its velocity be at z = 0.35 m? You may assume that the proton does not come to a stop before reaching the plane