A conservative force acts on a particle as the particle moves along the positive x-axis from origin to x=2m. The force is parallel to x-axis. Now, consider four different cases, as shown in the figures, 1, 2, 3 and 4, where the force is shown as a function of x. Rank the situations according to the change in potential energy associated with the force, least (or most negative) to greatest (or most positive)