如果绿色植物大量减少，大气中急剧增加并能够引起温室效应的气体是 A．氧气 B．氮

明确过期妊娠，胎儿宫内未见异常，无产科指征，处理原则为：

A．硫酸镁静脉滴注
B．盐酸哌替啶肌注
C．肼屈嗪静脉滴注
D．甘露醇静脉滴注
E．地西泮静脉滴注

有一瓶气体，它由H₂、CO₂、CO、CH₄中的一种或几种组成，用它进行以下实验：

①将气体通过足量澄清石灰水，未出现沉淀．

②在导管口将气体点燃，气体安静燃烧，火焰呈蓝色，用一个冷而干燥的烧杯罩在火焰上，烧杯壁上出现水珠；把烧杯迅速倒转过来，注入少量澄清石灰水，石灰水变浑浊．

用化学式回答问题：

（1）气体中一定没有______；

（2）气体的组成可能是（有几种可能就填几种，可不填满，也可补充）：

①______，②______，③______，④______，⑤______，⑥______．

（）皮肤的形成与缺乏维生素A有关。

A.中性

B.干性

C.油性

D.混合性

阅读理解

      No one wants to be tested. We would all like to get a driver' s license without answering questions

about rights of way or showing that we can parallel park a car. Many future lawyers and doctors

probably wish they could join their profession without taking an exam.

     But tests and standards are a necessary fact of life. They protect us from unskilled drivers, harmful

products and dishonest professionals. In schools too exams play a constructive role. They tell public

officials whether new school programs are making a difference and where new investments are likely to

pay off. They tell teachers what their students have learned -- and have not. They tell parents how their

children are doing compared with others of their age. They encourage students to make more effort.

     It is important to recall that for most of this century, educators used intelligence tests to decide which

children should get a high - quality education. The point of IQ testing was to find out how much children

were capable of learning rather than to test what they had actually learned. Based on IQ scores, millions

of children were assigned to dumbed-down programs instead of solid courses in science, math, history,

literature and foreign language.

     This history reminds us that tests should be used to improve education. Every child should have access

to a high-quality education. Students should have full opportunity to learn what will be tested; otherwise

their scores will merely reflect whether they come from an educated family.

     In the past few years, we have seen the enormous benefits that flow to disadvantaged students

because of the information provided by state tests. Those who fall behind are now getting extra instruction

in after-school classes and summer programs. In their efforts to improve student performance, states are

increasing teachers' salaries, testing new teachers and insisting on better teacher education.

     Performance in education means the mastery of both knowledge and skills. This is why it is reasonable

to test teachers to make sure they know their subject matter, as well as how to teach it to young children. And this is why it is reasonable to assess whether students are ready to advance to the next grade or

graduate from high school.

1. According to the passage, school exams enable ______.

A. teachers to understand if their students have made efforts

B. parents to compare their kids' behavior across schools

C. students to meet their teachers' requirements

D. governments to make right policies

2. "Dumbed - down programs" in Paragraph 3 refer to the programs which       .

A. lead to high-quality education  

B. are less academically challenging

C. are intended for intelligent students        

D. enable children to make steady progress

3. Which of the following does the author probably agree with?

A. Disadvantaged students can benefit from state tests.

B. Tests should focus on what students have actually learned.

C. Intelligent tests decide if children should get a high - quality education.

D. Intelligent tests are helpful in separating excellent students from poor ones.

4. What is the purpose of the passage?

A. To re-assess the value of IQ testing.

B. To defend the role of testing in education.

C. To explain what high-quality education means.

D. To call for thorough and complete reform in education.

当日平均气温降到连续5D在（）以下时，混凝土工程必须采用冬期施工技术措施。