The graph below depicts a firm with market power. In the graph, MC represents the firm's marginal costs, ATC represents the average total costs, D represents demand, and MR represents marginal revenue.

1. At 60 units of output, how much would this profit-maximizing monopolist charge?
2. How many units would it produce to maximize total revenue rather than total profit?
3. What is the maximum quantity this firm can produce without incurring economic losses?
4. Calculate the firm's profit at the profit-maximizing output and price.
5. Why is this firm's marginal revenue curve below its demand curve? Explain.