谵妄综合征的主要特征为（）
A.意识障碍昼轻夜重
B.幻觉
C.注意涣散
D.记忆减退
E.错觉
参考答案：A
某干线客运列车脱轨3辆，无人员伤亡应列为什么事故？
Which of the following is least accurate with regard to advertising for firms operating under monopolistic competition（）
A. The increase to average total costs associated with advertising increases as output increases.
B. Advertising expenses are high relative to perfect competition and monopoly.
C. Advertising is necessary to communicate the unique features of a firm’s products.
