一个四边形的一组对边平行但不相等，另一组对边相等但不平行，这个四边形是（ ） A．

下列说法正确的是（　　）

A．物体运动的加速度为零时，速度一定为零

B．物体运动的加速度减小，速度可能增大

C．物体运动的加速度不为零，速度一定不变

D．物体运动的加速度越来越小，速度变化可能越来越快

叙述并证明直线与平面垂直的判定定理.

某同学用分度值是lmm的刻度尺测量物理课本的长和宽，他记录的结果为：长25.4cm， 宽18.4cm，从这两个记录上就能看出他的测量不符合精确测量的要求，其错误是____________；还有一位同学也是用分度值为lmm的刻度尺测量的，记录的结果分别为：长25.631cm， 宽18.499cm，从这两个记录上也能看出他的测量错误，其错误是___________。

阅读理解。

     Secondhand smoke is a byproduct of cigarette, cigar or pipe smoking. Secondhand smoke occurs

when tobacco burns or when smokers exhale, and it is inhaled (吸入)involuntarily by non-smokers.

     Secondhand smoke___________________. The first is called side stream smoke, which is the

smoke released from the burning end of a cigarette or cigar, or from tobacco burning in the bowl of

a pipe. The second is called mainstream smoke, which is exhaled by a smoker.

     When nonsmokers are exposed to secondhand smoke, they inhale many of the same cancer-causing

chemicals that smokers inhale. According to the U.S. Surgeon General, cigarette smoke contains more

than 4,000 chemical compounds, including more than 50 cancer-causing chemicals, and at least 250

chemicals that are either toxic or carcinogenic.

     Both side stream and mainstream smoke are dangerous to nonsmokers. Side stream smoke is

generated at lower temperatures and under different conditions than mainstream smoke. As a result, it

contains higher concentrations of many of the toxins found in cigarette smoke.

     Secondhand smoke has been designated as a known human carcinogen by the U.S. Environmental

Protection Agency, the National Toxicology Program, and the International Agency for Research on

Cancer. Secondhand smoke also is listed as an occupational carcinogen by the National Institute for

Occupational Safety and Health.

     According to the 2006 report by the U.S. Surgeon General, there is no risk-free level of exposure

to secondhand smoke: even small amounts of secondhand smoke exposure can be harmful to people's

health. Separating smokers from nonsmokers, cleaning the air, and ventilating buildings can help.

However, they cannot eliminate the exposure of nonsmokers to secondhand smoke.

1.What is the main idea of the text? (no more than 10 words)

    _________________________________________________________ 

2. Which sentence in the text is closest in meaning to the following one?

In whatever way, people can’t get rid of the risk of nonsmokers to secondhand smoke

completely.

     _________________________________________________________

3. Fill in the blank in Paragraph 2 with proper words. (no more than 8 words)

     _________________________________________________________

4. Name at least three ways that will help reduce the harm of secondhand smoke.

  (no more than 12 words)

     _________________________________________________________

5. Translate the underlined sentence in Paragraph 3 into Chinese.

     _________________________________________________________

护理使用洋地黄的患儿时，以下叙述哪些是正确的( )。

A．每次给药前应数脉搏或听心率

B．患儿应单独服用洋地黄，不要与其他药物混合

C．如出现心率减慢、肝脏缩小、呼吸改善、尿量增加说明洋地黄有效

D．服用洋地黄时应避免使用排钾利尿药，以免钾低

E．如发现心率过缓、心律失常、恶心呕吐、视力模糊、色视、嗜睡、头晕，提示洋地黄中毒的可能，应先停药，报告医生处理