[单项选择]According to Olson, what is the reason for the poor economies of Third World countries A. government intervention B. lack of secure individual rights C. being short of capital D. lack of a free market
第21题: [单项选择]以下各项中,属于低钾血症典型EKG改变的是() A. ST段降低 B. Q-T间期变长 C. U波 D. T波变宽、降低、双向或倒置 E. QRS波变宽 参考答案:D 答案解析:低钾血症典型的心电图改变为早期出现T波降低、变平或倒置,随后出现ST段降低、QT间期延长和U波。故答案应选D。
第22题: [单项选择]关于鼻及鼻窦骨瘤的叙述,正确的是() A. 多发生于额窦,其次为筛窦 B. 多发生于上颌窦,其次为额窦 C. 多发生于筛窦,其次为额窦 D. 多发生于蝶窦,其次为筛窦 E. 多发生于上颌窦,其次为筛窦 参考答案:A
第27题: [单项选择]A. Invite his family to go to Alaska with him. B. Get advice on how to organize the trip. C. Make a flight reservation as soon as possible. D. Borrow money from his family. 参考答案:D 答案解析:[解析] M: I have to borrow enough money to buy a plane ticket.My archaeology class is taking a fie