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问题 选择题
数列{an}的通项公式an=
n+1
-
n
（n∈N*），若前n项的和Sn=10，则项数n为（　　）
A．10B．11C．120D．121
答案

∵an=

n+1
-
n
，

∴Sn=（

2
-1）+（
3
-
2
）+（
4
-
3
）+…+（
n+1
-
n
）

=

n+1
-1，

又Sn=10，

∴

n+1
-1=10，

∴n+1=112=121，

∴n=120．

故选C．

阅读理解与欣赏

阅读下面一段话，按要求答题。

在夏夜静谧的田野里，每个角落里都传出昆虫的歌唱。莹火虫在星光中跳着舞蹈，金钟儿的歌喉如同月光一般的qīng  cuì（ ），蟋蟀的歌声不太动听，但充满了热情，还有无数不知名的昆虫在吟唱，______________________（这里起来，那里下去。形容接连不断），无边无际，huì jù（ ）成了歌唱的海洋。

小题1:根据拼音在括号内写出相应的汉字。（２分）

qīng  cuì__________         huì jù__________

小题2:概括注释在横线处填写正确的成语。（1分）______________________

小题3:上段文字中有一个错别字，请找出，并改正。      改为        （1分）

小题4:这段描写主要运用了_________的修辞手法，表达了对宁静夏夜的赞美。（１分）
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单项选择题

For each blank, choose the best answer from the four choices and write down on the answer sheet.

It is claimed that Al applications have moved from laboratories to the real world. However, conventional von Neumann computers are (1) for Al applications, because they are de- signed mainly for numerical processing. In a larger yon Neumann computer, there is a larger ratio of memory to processing power and consequently it is even less efficient. This (2) remains no matter how fast we make the processor because the length of the computation becomes dominated by the time required to move data between (3) and memory. This is called the yon Neumann (4) . The bigger we build the machines, the worse it gets. The way to solve the problem is to diverse from the traditional architectures and to design special ones for Al applications. In the research of future Al architectures, we can take advantages of many (5) or currently emerging concepts. in computer architecture, such as dataflow computation, stack machines, tagging, pipelining, systolic array, multiprocessing, distributed processing, database machines, and inference machines.

4（）

A．problem

B．question

C．way

D．bottleneck
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