班级管理应该以学生为核心，建立学生为本的班级管理机制。（）

在一种叫做“蹦极跳”的运动中，游戏者身系着一根弹性优良的轻质柔软的橡皮绳，从高处由静止开始下落，到达最低点．在下落过程中，不计空气阻力，则以下说法中正确的是（　　）

A．游戏者的速度先增大后减小

B．游戏者的加速度先不变，再增大后减小

C．游戏者的加速度先不变，再减小后增大

D．当游戏者的速度达到最大时，加速度为零

“诗圣”指的是                          （    ）

A．李白

B．杜甫

C．李春

D．白居易

已知氨可以与灼热的氧化铜反应得到氮气和金属铜，用示意图中的装置可以实现该反应。

回答下列问题：

（1）A中加入的物质是___________________， 发生反应的化学方程式是______________________。

（2）B中加入的物质是___________________，其作用是_________________________。

（3）实验时在C中观察到的现象是____________________；发生反应的化学方程式是_______________。

（4）实验时在D中观察到的现象是_________________________， D中收集到的物质是_____________，检验该物质的方法和现象是__________________________________。

阅读理解。

     People are more likely to wash their hands properly after using the toilet if they are shamed into it

or think they are being watched, scientists said on Thursday.

     Hand-washing is the cheapest way of controlling disease but less than one third of men and two

thirds of women wash their hands with soap after going to the toilet, a British study by the London

School of Hygiene and Tropical Medicine showed.

     But when prompted by an electronic message flashing up on a board asking: "Is the person next

to you washing with soap?," around 12 percent more men and 11 percent more women used soap.

     Health authorities around the world are stepping up efforts to persuade people to be more hygienic

and wash their hands properly to help slow the spread of H1N1 swine flu, which was declared a

pandemic(大流行病) by the World Health Organization in June.

     "Hand-washing with soap has been ranked the most effective way for the worldwide control of

disease," the study's authors wrote.

     "It could save more than a million lives a year from diarrheal diseases, and prevent respiratory

(呼吸) infections -- the biggest causes of child mortality(死亡) in developing countries."

      In developed nations, hand-washing can help prevent the spread of viral infections like flu and

sickness and diarrhea bugs like norovirus and rotavirus, as well as hospital-acquired infections like

MRSA and C-difficile, the authors said.

     The researchers studied the behavior of a quarter of a million people using toilets at motorway

service stations in Britain over 32 days．Use of soap was monitored by sensors.

     The study, published in the American Journal of Public Health to mark Global Hand-washing

Day, showed that with no reminders, 32 percent of men and 64 percent of women used soap.

1．In which of the following situation can people wash their hands properly?

A．After they going to toilet．

B．when they think they are being watched.

C．When they think their hands are dirty.

D．When they find soap nearby.

2．Which of the following is the main advantage of hand-washing?

A．people can always get their hands clean．

B．People can save a lot of time and water．

C．It is the cheapest way of controlling disease.

D．It wastes no any time and energy.

3．What is the biggest cause of child death in developing countries?

A．respiratory infections．

B．diarrheal diseases．

C．H1N1 swine flu．

D．hospital-acquired infections.

4．Which of the following is true according to the seventh paragraph?

A．Hand-washing is popular in the developed countries.

B．They authorities persuaded the people to wash their hands daily.

C．More and more people know to wash their hands properly.

D．The spread of viral infections is a serious problem.

5．We can conclude from the passage that _______.

A．Most people wash their hands after going to toilet.

B．Many people can not wash their hands properly.

C．Few people know Global Hand-washing Day.

D．H1N1 swine flu was declared a pandemic.

《中国南方电网有限责任公司安全生产工作规定》要求反事故措施计划、安全技术劳动保护措施计划编制由谁组织？以什么部门为主？