The figure above shows a monopoly firm's demand curve. The monopoly's total revenue is zero at point

The domestic demand curve, domestic supply curve, and world supply curves for a good are given in the above figure. All the curves are linear. Initially, the country allows imports. Then imports are banned

Calculate how consumer and producer surplus change because of the ban. Is the country better off with the ban on imports? Why?

All monopolies exist because of:

a. firms' desire to maximize profits. b. failure of antitrust laws. c. barriers to entry. d. natural selection.