用一根长为12米的铁丝围成一个长方形．（1）使得该长方形的长比宽多2米，此时长

发布时间：2017-06-12 23:40 │ 来源：www.tikuol.com

题型：解答题

问题：

用一根长为12米的铁丝围成一个长方形．

（1）使得该长方形的长比宽多2米，此时长方形的长、宽各为多少米？面积为多少？

（2）使得该长方形的长比宽多1.6米，此时长方形的长、宽各为多少米？它所围成的长方形与（1）中所围长方形相比，面积有什么变化？

（3）使得该长方形的长与宽相等，即围成一个正方形，此时正方形的边长是多少米？它所围成的面积与（2）中的长方形面积相比又有什么变化？

考点：一元一次方程的应用

题型：解答题

阅读理解。

      Skin-diving (潜水) is a new sport today. This sport takes you to a new wonderful world. It is like a
visit to the moon! When you are under the water, it is easy for you to climb big rocks (岩石), because you
are no longer (不再) heavy.
      Here, under the water, everything is blue and green. During the day, there is enough light. When fish
swim nearby, you can catch them with your hands. When you have a tank (罐) of air on your back, you
can stay in deep (深) water for a long time. But you must be careful when you dive in deep water. To catch
fish is one of the most interesting parts of this sport.
      Besides (除此以外), there are more uses for skin-diving. You can clean ships without taking them out
of the water. You can get many things from the deep water. Now you see the skin-diving is useful and
interesting.

1. Skin-diving is going to take you to _____.

A. the deep water
B. be in danger
C. mountains

2. You can climb big rocks easily under the water because _____.

A. you are stronger
B. the fish nearby help you
C. you are lighter than on land

3. Under the water, a skin-diver _____ in the daytime.

A. can see everything clearly
B. can't see anything clearly
C. can see nothing

4. With a tank of air on your back, you can _____.

A. catch fish very easily
B. stay under the water for a long time
C. have more fun

5. From the passage we can know that skin-diving is _____.

A. harmful
B. not useful
C. useful and interesting

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干姜主治

A．回阳救逆
B．泻火解毒
C．渗利水湿
D．软坚散结
E．补益和中

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在某医院消化科的住院患者中，几天内突然发生多例医院感染。

医院感染研究的对象主要是（）

A.探视者

B.陪护者

C.急诊病人

D.门诊病人

E.住院病人

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保险代理从业人员的职业道德有( )。

A．诚实信用、守法遵规、专业胜任、勤勉尽责、保守秘密
B．诚实信用、爱岗遵规、专业胜任、勤勉尽责、保守秘密
C．诚实信用、守法遵规、专业精通、勤勉尽责、保守秘密
D．诚实信用、守法遵规、专业胜任、尽职尽责、保守秘密

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防爆移动式电气设备至少（）个月进行一次检查。

A.6

B.3

C.12

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