（）服务的主要用品包括：底油、彩色甲油、亮油、各种小吊饰、打孔钻、小镊子、尖嘴钳。A

2010年除夕之夜，小敏一家人坐在一起看电视。爷爷深有感触地说：“我年轻的时候，只能听广播。”爸爸说：“我年轻的时候，要跑到几里之外才能看上一场电影。”小敏说：“现在我可是秀才不出门，便知天下事！”妈妈兴奋地接话说：“现在的生活真是芝麻开花——节节高哇！”

根据以上材料，请回答：

（1）举例说明改革开放以来你家里生活发生的一些明显变化（提示：从衣食住行或家乡建设等方面举出两例即可。）

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（2）简要分析发生以上变化的主要原因。（三个方面即可。）

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When you think of all the ways your body can get hurt---falling off a bike, stepping on a nail, being bitten by a crazed dog---the aches and pains that come from sitting at a computer may not seem like much.

But more doctors are getting worried about just that. If you sit at a PC the wrong way, the nerves and muscles in your back, neck and arms can get out of line.

Ergonomics is the study of how people work and how jobs and equipment can be designed so that people are safer and more comfortable in the things they do---whether that’s working on a factory assembly line or sitting in front of a computer.

The monitor

You should not have to tilt（倾斜） your neck up or down to lock at the screen. Your eyes should be level with the top of the screen.

How far away should you sit? Reach your arm out so your fingertips just touch the screen.

The keyboard

It should be directly in front of you. Don’t unfold the legs on the bottom of the keyboard so that it tilts up toward you---it should be as flat as possible, or even tilted away from you. You want your wrists “neutral,” which means straight, not bent. This puts less strain on your nerves and muscles.

Arms should be close to the body. Don’t look at your fingers as you type. Use a document holder to hold papers at the same level as the monitor. Keep the mouse on the same level as the keyboard and close by--- so you don’t have to reach for it.

The chair

Your feet shouldn’t dangle---the blood will pool in your feet. They should rest flat on the floor, or on phone books, if necessary. Your back needs support. Roll up a towel and stick it there.

The Body

If you think of your body as a collection of right angles when you sit at a computer, you should be just fine.

Your hips should be at a 90-degree angle to your back. That takes the pressure off the spine. And your knees should bend at a 90 degree angle so your feet are flat.

小题1:The passage mainly talks about        .

A．avoiding pains caused by using PC

B．the science of ergonomics

C．illness caused by a computer

D．how to keep fit小题2:The underlined word “ergonomics” most probably means ______ in Chinese.  

A．管理学

B．人机工程学

C．机械工程学

D．经济学小题3:How high should a monitor be placed according to the passage?

A．As high as your arms.

B．A little higher than your eyes.

C．A little lower than your eyes.

D．At the same level as your eyes.小题4:How shouldn’t a keyboard be placed?

A．Tilting away from you.

B．Tilting up toward you.

C．Flat.

D．Not mentioned.小题5:How should you place your foot?

A．Rest them on a phone book.

B．Rest them on the floor.

C．They should rest flat.

D．They should dangle.

某研究性学习小组做探究“橡皮筋做的功和物体速度变化的关系”的实验，实验开始前，他们提出了以下几种猜想：①；②；③。实验装置如图所示，图中是小车在一条橡皮筋作用下弹出，沿木板滑行的情形，这时橡皮筋对小车做的功记为W。当我们用2条、3条……完全相同的橡皮筋并在一起进行第2次、第3次……实验时，每次橡皮筋都拉伸到同一位置释放。 小车在实验中获得的速度由打点计时器所打的纸带测出。

(1)实验时为了使小车只在橡皮筋作用下运动，应采取的措施是_________；

(2)每次实验得到的纸带上的点并不都是均匀的，为了计算出小车获得的速度，应选用纸带的__________部分进行测量；

(3)同学们设计了以下表格来记录数据。其中w₁、w₂、w₃、w₄，……表示橡皮筋对小车做的功。v₁、v₂、v₃、v₄、……表示物体每次获得的速度

他们根据实验数据绘制了如图乙所示的w-v图象，由图象形状得出结论。他们的做法是否合适？请说明理由：________________。

自然牙列前伸咬合时，如后牙有接触则视为（）。

卵丘的结构包括（）、（）和（）等。