搜题请搜索小程序“爱下问搜题”
问题 选择题

下列变化属于物理变化的是 （　　）

A．钢铁生锈

B．海水晒盐

C．工业炼铁

D．木柴取暖

答案

A、钢铁生锈的过程中有新物质生成，属于化学变化，故A错误；

B、海水晒盐的过程中没有新物质生成，只是发生了水的蒸发，属于物理变化，故B正确；

C、工业炼铁过程中，碳发生了反应生成了新物质，属于化学变化，故C错误；

D、木柴取暖的过程中木柴燃烧释放了热，生成了二氧化碳等，有新物质生成，属于化学变化，故D错误；

故选B．

完形填空

先通读下面的短文，掌握其大意，然后根据短文内容和所给首字母，在空格内填入一个适当的词，使短文意思完整。(共10小题；每小题0.5分，满分5分)

Tennis is in its second life. Its first game b小题1: in France. The name of the game comes from the French w小题2: "tennez". The English men c 小题3: the game "tennis" when they watched the Frenchmen play 800 years ago.

The Englishmen liked the French game. Tennis courts were b 小题4: in every park, in every city, just liketoday. The two countries played against each other. At first they played for h 小题5:. Then they won money. Later people began cheating（欺骗）to get money. Three hundred years ago the game was forbidden（禁止）to s 小题6: the cheating. The game also d_小题7:__. Americans found the old courts when they went to Europe 100 years ago. They learned w_小题8:_  they could do about the game. They liked the game as the Englishmen did before. After returning home, the Americans built tennis courts. Tennis began to become p小题9: in all the United States. Now it is one of the most e 小题10:games in the world again.
查看答案
多项选择题

男性，53岁，2年前被踢伤胸部，最近感胸部不适，常规胸片检查，示纵隔内病变，加扫CT平扫及增强，结果如图所示()

A．胸片示上纵隔见类圆形高密度影，以侧位片明显

B．CT增强扫描示主动脉弓层面左侧缘不规则，造影剂流入球形病灶内

C．结合临床，考虑为主动脉夹层

D．球形病灶外围见半月形低密度影，其内有斑片状高密度影，考虑为血栓形成

E．结合临床，考虑为主动脉假性动脉瘤(外伤性)
查看答案