As a Particle Moves Along the X Axis It Is

Multiple Choice

As a particle moves along the x axis it is acted upon by a single conservative force given by F_x = (20 - 4.0x) N where x is in m.The potential energy associated with this force has the value +30 J at the origin (x = 0) .What is the value of the potential energy at x = 4.0 m?

A) -48 J
B) +78 J
C) -18 J
D) +48 J
E) +80 J