Physician Supply: The supply of physician office visits is given by QS=40P-1000, and demand for physician office visits is QD=6000-60P. a. [2 points] If the market is perfectly competitive, what are the equilibrium price and quantity? b. [3 points] Suppose there is an entry barrier that prevents new physicians from entering the market, which limits QS ≤ 1200. What is the market price given this entry barrier? c. [3 points] How much total welfare (consumer surplus + producer surplus) is lost because of the entry barrier?