2008年元月，一场突如其来的特大冰雪灾害，袭击着我国南方地区，中国人民以气吞山

使用双铆钉枪、冲击式风顶或马蹄形铆钉机铆合时，铆合厚度可增至孔径的（）。

A、5倍

B、5.5倍

C、6倍

D、4倍

倾斜于投影面的面，其正投影面为扩大的面。

在探究杠杆平衡条件的实验中：

（1）小明发现杠杆右端低左端高，要使它在水平位置平衡，应将杠杆右端的平衡螺母向 ____ 调节．小明调节杠杆在水平位置平衡的主要目的是 _________________________________________

（2）实验过程中，在杠杆的两侧挂上钩码后，仍要使杠杆在水平位置平衡，是为了 _____________________________，如杠杆不在水平位置平衡时，应通过调节钩码的 ____ 和 _____ 来实现，而不能再调节 __________．

（3）如图所示，用弹簧测力计在C处竖直向上拉时测力计的示数为 ___N（每个钩码重0.5N），当弹簧测力计逐渐向右倾斜时，使杠杆仍然在水平位置平衡，则弹簧测力计的示数将_______ （选填“变大”、“变小”或“不变”），其原因是___________ ．

（4）某同学进行正确的实验操作后，得到的数据为F₁=6N、l₁=20cm、F₂=4N和l₂=30cm．该同学根据这些数据能否得出探究结论？_______．理由是：_______________________．

My grandfather took me to the fish pond on the farm when I was seven. He told me to throw a__21____into the water. And he told me to watch the____22___created by the stone. Then he asked me to__ 23__ of myself as that stone.

“You may24 lots of splashes (飞溅 ) in your life,___ 25___the waves that come from those splashes will ___26____the peace of all your fellow___27_____,”he said.

“Remember that you are ___28____for what you put in your circle and that the circle will also___29____many other circles. You will need to live in the ___30____that allows the good that comes from your circle to ___31____the peace of that goodness to___32____. The splash that comes from anger or jealousy will send those___33_____to other circles. You are responsible for____34_____.”

That was the first time I ___35_____each person creates the inner peace or discord (冲突) that ____36_____out into the world. We cannot create world peace if we are ___37____with inner conflicts, hatred, ____38______, or anger. We radiate (流露) the feelings and thoughts that we hold ____39_____,whether we speak them out or not. Whatever is splashing around inside of us is spilling out into the world, creating beauty or discord with all other circles of life.

We are ____40_____to everything and everyone else around in the universe.

21. A. stick    B. brick     C. stone      D. ball

22. A. holes    B. circles    C. drops      D. waters

23. A. think    B. accuse    C. regard     D. warn

24. A. produce  B. damage   C. prevent    D. create

25. A. but      B. because   C. while      D. for

26. A. cut      B. disturb    C. bring      D. block

27. A. students  B. friends    C. creatures   D. workers

28. A. proud    B. helpful    C. respectful   D. responsible

29. A. hear     B. leave      C. strike      D. touch

30. A. family   B. situation    C. way       D. hurry

31. A. send     B. provide    C. destroy     D. keep

32. A. them     B. nobody    C. someone    D. others

33. A. tastes     B. smells     C. feelings    D. views

34. A. all       B. both       C. neither     D. any

35. A. realized   B. recognized   C. admitted   D. promised

36. A. flows     B. takes       C. picks       D. brings

37. A. prepared   B. filled      C. presented    D. supplied

38. A. honesty    B. truth       C. doubt      D. modesty

39. A. forward    B. outside     C. inside      D. upward  

40. A. referred    B. intended    C. devoted    D. connected

创新型国家是指将科技创新作为基本战略，能够通过大幅度高科技创新能力，形成日益强大的竞争优势的国家，其科技进步贡献率在( )以上。

A．50%
B．60%
C．70%
D．80%