A Proton (Mass = 1

A proton (mass = 1.67 × 10⁻²⁷ kg, charge = 1.60 × 10⁻¹⁹ C) moves from point A to point B under the influence of an electrostatic force only. At point A the proton moves with a speed of 50 km/s. At point B the speed of the proton is 80 km/s. Determine the potential difference VB − VA.

A) +20 V
B) −20 V
C) −27 V
D) +27 V
E) −40 V