属于抗焦虑药的是 A．丁螺环酮 B．麦普替林 C．异羧肼 D．曲唑酮 E．硫利达嗪

患者男，76岁，已婚，退休。近半年来经常讲家中东西少了，被保姆和邻居偷窃了。常常半夜起来检查窗户、门锁是否已经关好，影响家人休息。怀疑妻子行为不轨，有外遇，经常打电话给子女告状，甚至与妻子争吵。心情不好。

该患者可能的诊断是（）

A.老年抑郁症

B.精神分裂症

C.偏执性精神病

D.老年痴呆

E.强迫症

小明用如图所示的一组实验来研究近视眼和远视眼的形成及矫正．

步骤一：如图（a）所示，调整蜡烛、凸透镜A和光屏的位置，直到在光屏上得到一个倒立，缩小的清晰的像为止．

步骤二：如图（b）所示，保持步骤一中蜡烛和光屏的位置不变，换用一个直径相同，但厚度比A小的凸透镜B．当把B放在原来A所在的位置时，光屏上不能成清晰的像，将光屏右移一定的距离，可得到清晰的像．

步骤三：如图（c）所示，步骤一中保持蜡烛和光屏的位置不变，换用一个直径相同，但厚度比A大的凸透镜C．当把C放在原来A所在的位置时，光屏上不能成清晰的像，将光屏左移一定的距离，可得到清晰的像．

（1）在步骤一中，蜡烛到凸透镜的距离u与凸透镜A的焦距f的关系必须满足______，此时光屏到凸透镜A的距离v与焦距f的关系为______．

（2）由______两图可说明近视眼的成因．

（3）由______两图可说明远视眼的成因．

（4）在进行步骤二时，若不向右移动光屏，但仍想要在光屏上得到清晰的像，可在凸透镜B的左侧相近的位置再放一只合适的______透镜．

（5）在进行步骤三时，若不向左移动光屏，但仍想要在光屏上得到清晰的像，可在凸透镜C的左侧相近的位置再放一只合适的______透镜．

旅游者在旅游活动中或者在解决纠纷时，损害旅行社、履行辅助人、旅游从业人员或者其他旅游者的合法权益的，依法承担赔偿责任

In 1998 consumers could purchase virtually anything over the Internet. Books, compact discs, and even stocks were available from World Wide Web Sites that seemed to spring up almost daily. A few years earlier, some people had predicted that consumers accustomed to shopping in stores would be reluctant to buy things that they could not see or touch in person. For a growing number of time-starved consumers, however, shopping from their home computer was proving to be a convenient alternative to driving to the store.

A research estimated that in 1998 US consumers would purchase $ 7.3 billion of goods over the Internet, double the 1997 total. Finding a bargain was getting easier, owing to the rise of online auctions and Web sites that did comparison shopping on the Internet for the best deal.

For all the consumer interest, retailing in cyberspace was still a largely unprofitable business, however. Internet pioneer Amazon. com, which began selling books in 1995 and later branched into recorded music and videos, posted revenue of $153.7 million in the third quarter, up from $37.9 minion in the same period of 1997. Overall, however, the company’s loss widened to $45.2 million from $9.6 million, and analysts did not expect the company to turn a profit until 2001. Despite the great loss, Amazon. com had a stock market value of many billions, reflecting investors’ optimism about the future of the industry.

Internet retailing appealed to investors because it provided an efficient means for reaching millions of consumers without having the cost of operating conventional stores with their armies of salespeople. Selling online carried its own risks, however. With so many companies competing for consumers’ attention, price competition was intense and profit margins thin or nonexistent. One video retailer sold the hit movie Titanic for $9.99, undercutting the $19.99 suggested retail price and losing about $6 on each copy sold. With Internet retailing still in its initial stage; companies seemed willing to absorb such losses in an attempt to establish a dominant market position.

Finding a bargain on the Internet was getting easier partly because（）

A. there were more and more online auctions

B. there were more and more Internet users

C. the consumers had more money to spend

D. there were more goods available on the Internet

简述温度计的测温原理？