If in midst of a traffic jam, a new lane just opened up in Lake Shore Drive and there are no cars moving to the new lane yet, is the traffic in equilibrium?

a) Yes, because some cars would be better off by moving to the other lane

b) No, because some cars would be better off by moving to the other lane

c) No, because efficiency and equity are at odds

d) Yes, because the equilibrium never changes regardless of changes in original conditions