A monopolistically competitve firm may earn abnormally high profits in the

short term, but the process of the entry will drive those profits to zero in the long run

long term, but the process of entry will drive those profits to zero in the short run

short run, but after the entry occurs, the long term percieved demand curve shifts to the right.

long run, but after the entry occurs, the short term percieved demand curve shifts to the right