In the system shown below, there are 80 x particles, all in region a (the left half of the box). no extra particles can enter the system. when the system is in equilibrium, what will be true of the particles? a. since there are no y particles, the system is already in equilibrium with all 80 x particles in a. b. due to the constant motion of particles, this system will never reach equilibrium. c. in equilibrium, there will be exactly 40 x particles in a and 40 x particles in b, and those numbers will remain constant. d. in equilibrium, there will be approximately 40 x particles in a and 40 x particles in b, and those numbers will fluctuate but will remain near 40.