搜题请搜索小程序“爱下问搜题”
问题 选择题

下列运算中，与a•a5的结果相同的是（　　）

A．a3+a5

B．a2•a3

C．（a3）2

D．（a2）3÷a

答案

原式a•a5=a1+5=a6．

A、a3与a5不是同类项，不能合并，故本选项错误；

B、应为a2•a3=a5，故本选项错误；

C、（a3）2=（a3）2=a3×2=a6，正确；

D、应为（a2）3÷a=a6÷a=a5，故本选项错误．

故选C．

完形填空

第二节语法填空（共10题；每小题1.5分, 满分15分）

阅读下面短文，根据上下文填入适当的词语，或使用括号中的词语的适当形式填空,并将答案填写在答题卡上标号为31—40的相应位置。

Money really can’t buy happiness. According to a new survey, lawyers and __31_____ well-paid white-collar workers are more likely to suffer depression. A national survey of more than 7500 professionals has found that almost one __32_____ ten reported moderate (中度) to severe depressive symptoms. The legal profession had the worst result, _33_______ almost 16 percent reporting symptoms of clinical depression (临床抑郁症). Next __34_____(be) accountants and insurance underwriters, both on 10 percent. People in IT services, architecture and engineering also had depression rates above the average.

The survey __35_____ (conduct) by Beyondblue, an organization devoted to fighting depression, also showed that __36_____ under 30 who had the __37_____ (high) rates of depression were the most likely to “self-medicate” with drugs and alcohol. Beyondblue deputy chief executive and _38_________ (psychology), Dr. Nicole Highet, said the survey was first to reveal the extent of the problem. “We often associate depression with the most socially disadvantaged and people under financial pressure, __39_____ here’s a whole different group.” Dr. Highet said, She said while it was difficult to know exactly __40________ made some groups more prone to depression, it was likely to be driven by work pressures.

查看答案
多项选择题

淋巴系统主要包括（）。

A.淋巴结

B.淋巴管道

C.淋巴器官

D.淋巴干

E.淋巴组织
查看答案