Final answer:
In a monopolistically competitive market, price does not equal marginal revenue for all output levels, but price does equal average revenue for all output levels. Additionally, marginal revenue equals marginal cost at the profit-maximizing output.
Step-by-step explanation:
A monopolistically competitive firm operates in a market structure where there are many sellers offering differentiated products. In contrast to a perfectly competitive firm, a monopolistically competitive firm does not have price equal to marginal cost for all output levels. Therefore, statement 1) is true. While marginal revenue is equal to price for a perfectly competitive firm, for a monopolistically competitive firm, price does not equal marginal revenue for all output levels. Hence, statement 2) is true. However, price does equal average revenue for all output levels in both perfectly competitive and monopolistically competitive markets. Therefore, statement 3) is false. Lastly, just like a perfectly competitive firm, a monopolistically competitive firm maximizes profit by setting marginal revenue equal to marginal cost at the profit-maximizing output. Thus, statement 4) is true.