根据下列事实所作的结论,正确的是 编号事实结论A甲、乙两种有机物具有相同相对分子

题型:选择题

问题:

根据下列事实所作的结论,正确的是

编号事实结论
A甲、乙两种有机物具有相同相对分子质量和不同结构。甲和乙一定是同分异构体。
B质量相同的甲、乙两种有机物完全燃烧时产生质量相同的水。甲、乙两种分子中,各元素的原子个数比一定相同。
C在苯酚钠的水溶液中通入少量二氧化碳,溶液中出现浑浊。生成碳酸钠和苯酚,说明碳酸的酸性比苯酚强。
D不存在两种邻二甲苯。苯分子中碳碳键完全相同,而不是单双键交替结构。

考点:结构简式结构式
题型:选择题
把下列语段中拼音所表示的汉字和划线字的注音依次写在文后方格内。(2分)
有这样一首kuài(  )炙人口的散文诗:“在疑惑不安的日子里,在痛苦思念我祖国命运的日子里,给我鼓舞和支持的,只有那真zhì(  )的、zhōng(  )爱深谙(  )的母语!是它给了我们希望和力量,我们决不能亵(  )渎自己的母语。”  (《汉字的魅力》)
汉字
 
 
 
注音
 
 
 
题型:选择题

下列说法正确的是(  )

A.静止的物体,如果受到推力的作用,它的运动状态一定发生改变

B.两个力大小相等、方向相反且作用在一条直线上,这两个力可能是平衡力

C.如果作用在物体上的两个力的三要素都相同,这两个力可能是平衡力

D.做匀速直线运动的物体只受到一对平衡力的作用,如果突然失去其中一个力,则该物体可能不再做直线运动

题型:选择题

下列关于E-R图的描述中正确的是( )。

A.E-R图只能表示实体之间的联系

B.E-R图只能表示实体和实体之间的联系

C.E-R图只能表示实体和属性

D.E-R图能表示实体、属性和实体之间的联系

题型:选择题

皮下埋植避孕(norplant)的放置时间为

A.月经周期第14天

B.月经干净3~7天

C.月经干净3~5天

D.月经期1~7天

E.经前期第7天

题型:选择题

阅读理解

     A bad Working Memory-the brain's temporary storage box-may explain,   new research suggests,  

why one child cannot read his or her history book and another gets lost in math. As many as 10 percent

of schoolage children may suffer from poor working memory. British researchers said in a report last

week,   yet the problem is rarely identified.

     "You can think of working memory as a pure measure of your child's potential. Many psychologists

consider working memory to be the new IQ (智商),   because we find that working memory is one of

the most important predictors of learning ability,   " said Dr. Tracey Alloway of Britain's Durham

University.

     Many children with poor working memory are considered lazy or dull. Working memory allows people

to hold in their minds and deal with a few items,   such as telephone numbers,   over a short period of

time. Alloway compares working memory to a box. For adults,   the basic box size is thought to be three

to five items. It's important,   therefore,   to put in the right things. Irrelevant (不相关的) information will

clutter (混乱) working memory.

     The question many researchers are struggling with is how to help children with this problem,   which

appears to be closely related to a lack of attention.

     "In children with learning difficulties,   it becomes a huge issue,   especially around middle school,  

when the demands on working memory really grow,   " said Dr. Mel Levine,   cofounder of All Kinds

of Minds,   a nonprofit organization in North Carolina that studies learning difficulties.

     Memory training may help improve working memory. Alloway has a tool that allows teachers to

assess (评定) the workingmemory capacity of children as young as 4; it has been used in 35 schools

across Britain.

     Levine's organization trains teachers through a program called Schools Attuned,   which is working

with several thousand schools across the United States,   Canada and Europe. While he is not sure

working memory can be expanded,   Levine said children can be taught ways to do better in school.

1. Which of the following is a characteristic of working memory?

A. It has a limited capacity.

B. It is usually better in children than adults.

C. It improves with use.

D. It can cause a lack of attention.

2. According to the new research,   ________.

A. the importance of working memory has been long recognized

B. working memory is becoming recognized as a factor in intelligence

C. laziness can weaken working memory

D. working memory helps people remember things forever

3. Which of the following may help improve a child's working memory?

A. Expanding the brain's storage box.

B. Remembering more things.

C. Training the memory.

D. Being reminded frequently.

4. According to the passage,   Dr. Mel Levine has ________.

A. invented tools to help improve a child's working memory

B. founded an organization to train teachers to help students with this problem

C. identified the problem clearly

D. compared working memory to a box

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