Monopolist Question

Why does a monopolist have the best chance of making a long run economic profit? What about the monopolistic cost structure make them candidates for a long-run economic profit?

need to solve the following problem

A monopolist with a straight-line demand curve finds that it can sell two units at $12 each or 12 units at $2 each. Its fixed cost is $20 and its marginal cost is constant at $3 per unit. a. Draw the MC(marginal cost), ATC (average-total-cost), MR (marginal revenue), and demand curves for this monopolist. b. At what output level would the monopolist produce? c. At what output level would a perfectly competitive firm produce?

Monopolistic Competitor (In Equilibrium - what will be output choice? What will be average fixed cost?)

1. Suppose a monopolistic competitor in long-run equilibrium has a constant marginal cost of $6 and faces the demand curve given in the following table (see attachment). a) What output will the firm choose? b) What will be the monopolistic competitor's average fixed cost at the output it chooses?

need to solve the following problem

Why does producing at MC=MR maximize profit for a monopolistic competitor?

need to solve the following problem

I need two examples of companies within each market structure (Perfect Competition, Monopolistic Competition, Monopoly, Oligopoly), and the explaination why you feel that they belong there.