Final answer:
A monopolist produces in the elastic portion of the demand curve to maximize revenues, differing from perfect competitors who face a perfectly elastic demand curve.
Step-by-step explanation:
A monopolist produces in the elastic portion of the demand curve. This is because in the inelastic portion, raising prices would lead to a less than proportional decrease in quantity demanded, which would not maximize revenue. In the elastic portion of the demand curve, however, a monopolist can increase revenues by lowering prices since the percentage increase in the quantity sold is greater than the percentage decrease in price.
When comparing to other market structures, a perfect competitor faces a perfectly elastic demand curve, indicating infinite elasticity, while a monopolistically competitive firm's demand curve is more elastic than a monopoly's but not perfectly so, showing a range of responsiveness between the two extremes.