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问题 填空题

在北方家庭蒸常用到纯碱，它的晶体（Na2CO3•10H2O）的相对分子质量是______．

答案

由晶体的化学式为Na2CO3•10H2O，

则该晶体的相对分子质量为，23×2+12+16×3+10×（1×2+16）=286，

故答案为：286．

单项选择题 共用题干题

患者女，58岁，因“乏力、背痛1个月”入院。查体：左肺呼吸音低，叩诊浊音。患者6个月前曾因头部皮肤恶性黑色素瘤行手术切除，术后经化学治疗。胸部CT：左侧胸膜多发结节影突向胸腔内，左侧少量胸腔积液。

最有助于明确诊断的检查是（）

A.MRI

B.PET-CT

C.胸腔积液检查

D.经皮穿刺胸膜活检

E.经VATS胸膜活检
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单项选择题

Questions 61—65 are based on Passage Two:Passage TwoAs the 21st century begins, a number of leaders in politics, education, and other professions believe that the US must adopt some new values to go along with the old traditional ones. What new values should Americans adopt This is a very difficult question to answer. Certainly, a greater value should be placed on the conservation of natural reasources; Americans should learn to use less and waste less. But conservation has never been a p value to Americans, who have believed that their country offered an endless,abundant supply of natural resources.Recently, progress has been made—more and more Americans are recycling their paper,cans,bottles,and other goods—but old wasteful habits died hard. Furthermore,the need to protect the environment may conflict with the need for jobs,as in the Northwest ,where conservationists battle lumber companies that want to cut down ancient redwood trees. A belief in the value of conservation is still compared with other American values; it can become per only as Americans see the need for it more clearly.In addition,Americans may need to place a p value on cooperation on a national scale to achieve important national objectives. The American idea of the national good has never been based on national cooperation but rather on the freedom of the individual, maintaining those conditions that provide the greatest freedom and prosperity for the individual . It is far more difficult for Americans to accept shared sacrifice for the common good and wellbeing of the entire country. For example ,although the majority of Americans believe that it is extremely important to balance the national budget and reduce the deficit, they do not want to see cuts in government programs that benefit them personally.The American value of competition also hinders the development of a spirit of national cooperation. Competition sometimes encourages feelings of suspicion rather than the mutual trust that is necessary for successful national cooperation.Although Americans often cooperate successfully on the local level—in neighborhood groups and churches, for example, on the national level, they may see themselves as part of an interest group that is competing with other interest groups for government funds. A request by the national government for shared sacrifice may be seen as coercive and destructive rather than voluntary and constructive. However, the demands for the 21st century may compel Americans to place a greater value on national cooperation to solve problems that affect them all, directly and indirectly.

What is the basis for the American notion of national good()

A．Individual freedom.

B．Personal property.

C．National cooperation.

D．Both A and B.
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