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问题 填空题
若x2+kx+
1
16
是一个完全平方式，则k=______．当m=______时，25x2-20xy+my2是完全平方式．
答案

x2+kx+

1
16
可化为k2+kx+（
1
4
）2；可见k=±
1
2
；

当25x2-20xy+my2时，有（5x）2-20xy+（±2y）2，可见，m=±2．

故答案为±

1
2
，±2．

阅读理解

任务型阅读。

      My name is Carl. I have a good friend . His name is Ding Ding . We live in the same dormitory.

He is polite when he meets teachers, he always says " hello " to them. And he likes smiling very much.

      His smiling face makes us happy. He likes helping others, too, Look! There's an old woman

carrying a heavy box . He runs to her and says " Can I help you ? "

     "No, thanks." the woman answers. "I can do it by myself. "

      Why does she say that? Because older people in America don't think they need a lot of help.

1. Ding Ding comes from                              .

2. Carl                              with Ding Ding.

3. People like seeing Ding Ding's                               face.

4. The old woman is carrying a                               box.

5. The woman                              want Ding Ding to help her.

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单项选择题

根据我国《建筑法》的规定，下列行为属于未禁止行为的是（）。

A．施工企业允许其他单位使用本企业的营业执照，以本企业的名义承揽工程

B．总承包单位自行将其承揽工程中的部分工程发包给有相应资质条件的分包单位

C．两个以上的承包单位联合承包大型或结构复杂的建筑工程

D．分包单位将承包的工程根据工程实际再分包给具有相应资质条件的分包单位
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