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问题 选择题

正确的实验操作是获得正确的实验结果和保障人身安全的前提．下图所示的实验操作正确的是（　　）

A．闻气味

B．拿走蒸发皿

C．倾倒液体

D．稀释浓硫酸

答案

A、为了人的安全，要用所谓的招气入鼻法来闻，就是打开试剂瓶后，拿到距离20CM左右的地方，用手把瓶口的气体往自己的方向扇．故A选项不正确；

B、为不至于烫伤手，不能直接用手从燃着的酒精灯上拿走蒸发皿，而应用镊子夹取．故选项B不正确；

C、取用细口瓶里的液体药品是，要先拿下瓶塞，倒放在桌面上，，标签对准手心，瓶口与试管口挨紧．故C选项正确；

D、浓硫酸具有腐蚀强性，为了避免使酸骤热溅出对人造成伤害，应把浓硫酸慢慢往水里到，用玻璃棒不断摇匀．故D选项不正确．

故选C

填空题

B The Culture Debate in the US:Whose Culture Is This ,Anyway 美国的文化辩论：空间是谁的文化？
Part of the debate about culture revolves around issues of perspective and ownership. Within a nation such (1) the United States—a nation whose cultural heritage includes elements from every corner of the world (2) are a great many perspectives coexisting and intertwining in the cultural fabriC．When we all ask (3) as individuals, "what belongs to me, to my culture " we are rewarded with a spectacular variety of (4) ; in this way, different perspectives and ownership of different cultural traditions enriches everyone. But when we ask " (5) belongs to us, to our culture " we ask a much harder question. Do the people of the (6) States, or of any culturally complex human society, necessarily share common cultural elements If so, who gets (7) decide what those elements are
This debate is a crucial one in many cultures throughout the world (8) . In the US, the debate promises to impact the way we educate our children—that is, (9) manner and shape in which culture reproduces itself—and the way we write our laws. In (10) countries, equally crucial issues are at stake.
For many people, what is at stake is the character (11) US national identity. Hirsch argues that this identity needs to become less culturally fragmented; others, like Walker, (12) that the national character gets its strength from cultural diversity, from the freedom (at home and in (13) ) to celebrate, honor, and reproduce different cultural traditions. Those who take this latter view follow the reasoning (14) Shweder, arguing that we need to accept that there are multiple valid cultural perspectives and that two (15) perspectives can both be valid even though they might contradict one another.
Recognize that the position you (16) in this debate about culture—whatever position you take—is a political one with implications (17) what we should value, what we should praise, what we should accept, what we should teach. When (18) reflect on this debate, when you contribute your own voice to the discussion, try to be (19) of the implications that follow from your position. When you listen to the voices of others, try to (20) with awareness, deciding for yourself what is at stake and how their positions relate to your own.

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判断题

钙石灰比镁石灰稳定材料的初期强度高，特别是在剂量不大的情况下，但镁石灰稳定材料的后期效果并不比钙石灰差，尤其是在剂量较大时，还优于钙石灰。石灰的等级越高(即CaO+MgO的含量越高)时，在同样石灰剂量下有较多的CaO和MgO起作用，因而稳定效果越好。
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