Which of the following statements about monopolists is most likely correct（）
A. Without government intervention, monopolists will always earn profits.
B. A monopolist maximizes price where marginal revenue equals marginal cost.
C. Monopolists have imperfect information about demand.
参考答案：C
解析：
Demand curves are not observable so a monopolist must search for the profit maximizing price. Because demand information is not perfect, a monopolist is a price searcher. The other statements are false. Although a monopolist can earn positive economic profits in the long run, they are not guaranteed profit. If average total costs exceed price, the monopolist will lose money. A monopolist maximizes profit where marginal revenue equals marginal cost. A monopoly may be defined as a single seller of a well-defined product for which there are no good substitutes.
；E.电流表A2：量程为0~0.6A，内阻约为0.6
曲线。
