这个标志的含义是提醒前方右侧行车道或路面变窄。

如图所示，水平地面上有、两点，点和点分别在点和点的正上方，距离地面高度分别为和．某时刻在点以速度水平抛出一小球，经过一段时间后又从点以速度水平抛出另一球，结果两球同时落在、连线上的点，则有（ ）

A．

B．

C．

D．

根据我国继承法的规定，祖父母、外祖父母是孙子女、外孙子女的（　　　）

A．第一顺序法定继承人

B．第二顺序法定继承人

C．第三顺序法定继承人

D．第四顺序法定继承人

患者，男，55岁，右睑下垂1年，四肢无力6个月，呼吸困难3天。四肢无力具有晨轻暮重的特点。无复视，无吞咽困难及构音障碍。3天前因上呼吸道感染出现呼吸费力。既往有高血压病史5年，糖尿病史2年。查体：呼吸频率35次／分，呼吸表浅，口唇略发绀，右侧睑裂小，四肢肌力四级，疲劳试验阳性，余神经系统查体未见明显异常。胸部CT显示胸腺增生。肌电图提示右腋神经低频重复电刺激波幅递减。血气分析显示，pH7.30，Osat85%，PCO₂68mmHg，PO₂55mmHg。

该患者的治疗首选（）

A.免疫抑制剂

B.胸腺摘除

C.气管切开，呼吸机辅助呼吸

D.使用抗生素

E.激素冲击

第二节（共5小题；每小题2分，满分10分）

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

There were times when it was only schoolchildren who felt sick before they got their grades.

71 

Many teachers are opposed to it. They don’t mind being evaluated. But they are upset because the results are then being posted on the Internet and accessible to millions of Internet users.   72  The teachers are graded on categories such as “motivated”, “good instruction”, “easy examinations”, or even “sexy”.   73 

The creators of the website say that the students are only being offered the chance to provide teachers with some feedback(反馈)about their classroom instruction. Bernd Dicks founded the website with three friends.   74  On a grading scale of one to six, the teachers’ average grade is as high as 2.7 and it has been improving lately. He often says the impression is that students are bullying(欺负)their teachers. But there is also bullying of the students by teachers.

“Teachers must also learn to live with criticism,” he added. But still, the website is not totally prevented from being manipulated(人为操纵), as one teacher near the northern city of Hanover recently proved.   75  Within a few days, seven of his colleagues were listed in the top 10 rankings of Germany’s best teachers.

On the website www. spickmich. De during the past four months students have posted evaluations of 100,000 teachers.

A．He registered himself on the website as a student and then rated his own teaching colleagues highly.

B．Many teachers think that their privacy has been disturbed.

C．But now teachers in Germany are scared, too, as they are being graded by their students.

D．He says that the students are largely quite satisfied with their teachers.E.He says a majority of the students expressed their dissatisfaction with their teachers.

F.He tried to make friends with students as many as possible.

将一定量铁粉和铜粉的混合物加入由稀H₂SO₄和HNO₃组成的混合溶液中，充分反应后金属粉末有剩余，下列有关推断正确的是（　　）

A．反应过程中不可能产生H₂

B．剩余的金属粉末中一定有铜

C．往反应后的溶液中加入KSCN溶液会变血红色

D．往反应后的溶液中加入足量的稀H₂SO₄，则金属粉末的质量一定会减少