The November 2017 iPhone X and October 2018 iPhone XS have been regarded as Apple Com- puter's first smartphone models with innovations that fail to impress compared to the innovations of its previous models. In a monopolistically competitive industry like smartphone handsets, show through a diagram and explanation, how the quantity produced by a firm in the long run compares to the quantity a perfect competitor would produce? Are the levels of product development and eorts to advertise product dierences greater than the ecient level in monopolistically competitive industries