等差数列{an}的通项公式是an=-n+5，则此数列的公差为______．

阅读理解。回答问题。

     One day, I went to visit my aunt. When I was playing outside with the kids from the neighborhood, I

 saw a lovely dog. I was very happy and tried to catch it. But the dog ran away in the woods (树林). I ran

  after it and forgot my aunt's words -not to go far.

     Finally, I caught the dog. But when I looked around, I noticed that everything around me was dark and

  strange. I felt frightened and a little hungry.

     I walked for a long time, but I still couldn't find my way home. I was very tired and sat under a tree.

 Suddenly, I found that the dog was missing again. At that moment, a policeman appeared (出现) in front

  of me, sitting on a motorbike with the dog. He said the dog took him there and then he drove me back to

  my aunt's house.

     I felt thankful to the dog and gave it some delicious bones. Then I set it free again. Who knows, maybe

  it would help out another little lost boy back to his family. 

1. Who did the writer play with at first?

     ______________________

2. What did the writer's aunt tell him? 

    ______________________

3. What was like in the woods?

    ______________________

4. How did the writer come back to his aunt's home?

    ______________________

5. Did the writer keep the dog at home from then on? 

    ______________________

下列不是房地产报告摘要需要指出的问题的是( )。

A．调研的目标

B．时间、地点、对象、范围

C．限制的条件

D．执行的结果

狭义“历史”二者间（人类客观的历史与历史撰述）的关系如何？

求职简历中个人信息撰写的原则是（）。

A、简洁

B、突出优势信息

C、尽可能详细

D、直观

计算机手段制作课件的基本步骤有选题、教学设计、（）、程序设计、开发及测试。

A.设备调整

B.脚本制作

C.资源整合

D.信息收集