Aproton is traveling horizontally to the right at 4.20×10^6m/s. part a: find (a)the magnitude and (b) direction of the weakest electric field that can bring the proton uniformly to rest over a distance of 3.50cm. part b: counterclockwise from the left directionpart c: how much time does it take the proton to stop after entering the field? part d: what minimum field ((a)magnitude and (b)direction) would be needed to stop an electron under the conditions of part (a)