仔细观察与阅读下面表格中的人物感受与文字说明，并回答问题：

如图所示，小谢在探究“杠杆的平衡条件”实验中所用的实验器材有：杠杆、支架、    弹簧测力计、刻度尺、细线和质量相同的钩码若干个。

（1）实验前，将杠杆中点置于支架上（如图甲），
当杠杆静止时，发现杠杆右端下沉。此时应把杠杆两端
的平衡螺母向____ （选填“左”或“右”）调节，使杠杆在
不挂钩码时，保持____ （选填“水平”或“倾斜”）并静止，
达到平衡状态。这样做的好处是：便于在杠杆上直接测量____ 
（2）杠杆调节平衡后，小谢在杠杆上A 点处挂3个钩码，
在B 点处挂2个钩码，杠杆恰好在原位置平衡。于是小谢便得出了杠杆的平衡条件为：____ （用公式表示）。她这样得出的结论是否合理？____ （选填“合理”或“不合理”）；为什么？____ 。
（3）实验结束后，小谢提出了新的探究问题：“若支点不在杠杆的中点时，杠杆的平衡条件是否仍然成立？”于是小组同学利用图乙所示装置进行探究，发现在杠杆右端的不同位置，用弹簧测力计竖直向上拉杠杆使其处于平衡状态时，测出的拉力大小都与杠杆平衡条件不相符。其原因是：____ 

阅读理解

What Will Be Done-With All This Denim?

    All the denim (牛仔布) will be donated to Cotton From Blue to Green, which recycles jeans into UltraTouch Natural Cotton Fiber Insulation (纤维隔热材料), which is used to help build houses in places that have been damaged by hurricanes and other natural disasters. Your jeans will help keep clothes out of landfills (垃圾场), and build houses for families to live in! UltraTouch is made of 85% recycled fibers and is an environmentally safe, natural cotton fiber insulation.

It's a Fact

    It takes about 500 pairs of jeans to recycle enough denim to insulate one average-size U.S house.

Here's How You Can Get Involved!

1). Get a parent's permission and select as many denim jeans as you like. (Any denim clothing is OK)

2). The denim must be used.

3). The denim can be any brand.

4). The denim can be any color or size but must have been worn by a human (no doll clothes!).

5). Jeans must be received by June 30, 2017.

    By donating denim, you can give it a “new life” by converting it into UltraTouch Natural Cotton Fiber Insulation. Click here for more information about the denim drive.

    UltraTouch is composed of 85% recycled fibers and is an environmentally safe, non- itch natural cotton fiber insulation. For more information about UltraTouch, click here.

—So it is. Many trees       on the hill every year.

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