A monopoly has an inverse demand curve of P = 450-50 and marginal cost of MC = 400, where Q is the level of output produced. The monopolist chooses to sell 9 units of output at a price of $405 per unit to maximize profits. What is the deadweight loss at the firm's profit-maximizing output level? a) $20. b) $202.5 c) $0. d) $22.5