please help with physics problem! photo attached?

kinetic energy gained = work done by the electric field (conservation of energy, 1st law of thermodynamics)

this is the easiest way to model the problem.

(*)Work done by the electric field = charge of proton x electric field strength x displacement

= 1.602 x 10-19 C x 70000 x 0.2

= 8.73 x 10^-16 J

= 8.7 x 10^-16 J (2 significant figures)

as described at the start, from conservation of energy, this is equal to the amount of kinetic energy gained by the proton.

(*) this formula is obtained from Word done by an electric field = charge x change in potential difference

in this case, change in potential difference = electric field strength x displacement.

the displacement is quite easy to calculate as the displacement (0.2m) is in the same direction as the electric field (and the field direction shows the path a positive charge is influence, and the proton is positively charged), so we don't need to change signs.