c.若政府管制價格為P=35 ’市場上的均衡交易量為何？（5%)

a. If De Beers charges the monopoly price, what is the monopoly price? How large is the individual consumer surplus that each buyer experiences at this monopoly price? Calculate total consumer surplus by summing (lie individual consumer surpluses. How large is producer surplus? (10%) Suppose that upstart Russian and Asian producers enter the market and the market becomes perfectly competitive.