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问题 填空题

已知等差数列an中，且a3+a7=10，则S9=______．

答案

根据等差数列的性质可得，a3+a7=a1+a9=10

∴s9=

9(a1+a9)
2
=45

故答案为：45

阅读理解与欣赏

       远山无脚，远树无根，远舟无身，也是造园之理。园林中的每一个观赏点，看去都是一幅幅不同的画，要深远而有层次。“常倚曲阑贪看水，不安四壁怕遮山”。如能懂得这些道理，适宜敞开的地方敞开，适宜遮蔽的地方遮蔽，适宜分隔的地方就要分隔，等等。让游览者只见片段，不漏全形。这样，画外有画，咫尺千里，余味无穷。

1、文章强调园林的景致要_______________________。

2、苏州园林是世界文化遗产之一，我们欢迎更多的人到苏州园林参观游览，请为苏州园林拟写一句广告语。

   ________________________________________________________
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单项选择题

The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable (16) of the technical requirements for the software product.

During the requirements definition phase, the requirements definition team uses an iterative process to expand a broad statement of the system requirements into a complete and detailed specification of each function that the software must perform and each _( 17) that it must meet. The starting point is usually a set of high level requirements from the (18) that describe the project or problem.

In either case, the requirements definition team formulates an overall concept for the system and then defines (19) showing how the system will be operated publishes the system and operations concept document and conducts a system concept review (SCR).

Following the SCR, the team derives (20) requirements for the system from the high level requirements and the system and operations concept. Using structured or object-oriented analysis, the team specifies the software functions and algorithms needed to satisfy each detailed requirement.

19（）

A.rules

B.principles

C.scenarios

D.scenes
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