石墨烯是由碳原子构成的单层片状结构的新材料(结构示意图如下),可由石墨剥离而成,

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问题:

石墨烯是由碳原子构成的单层片状结构的新材料(结构示意图如下),可由石墨剥离而成,具有极好的应用前景。下列说法正确的是

[ ]

A.石墨烯与石墨互为同位素

B.0.12g石墨烯中含有6.02×1022个碳原子

C.石墨烯是一种有机物

D.石墨烯中的碳原子间以共价键结合

考点:共价键阿伏加德罗常数同位素
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计算:(-2)×(-4)=        

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如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,由自由电子和阳离子构成,整体呈电中性)从左侧进入,在t时间内有n个自由电子落在B板上,则关于R中的电流大小及方向判断正确的是(  )

A.I= ,从上向下

B.I= ,从上向下

C.I= ,从下向上

D.I= ,从下向上

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某客户于2008年8月向某特种汽车制造厂(增值税一般纳税人)定购自用小汽车一辆,按客户要求加装1厘米厚度钢板作车壳,加装排量为 15.2升的发动机,客户支付车款(含税) 1055500元,另付钢板费1.8万元,电脑三维测试安全系数费0.98万元。该辆汽车应缴纳消费税为( )。(消费税税率为20%)

A.214359元

B.92589.74元

C.150800元

D.185179.49元

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申请证券评级业务许可的资信评级机构应当具备的条件有()。

Ⅰ.具有中国法人资格,实收资本与净资产均不少于人民币2000万元

Ⅱ.具有符合规定的高级管理人员不少于3人

Ⅲ.最近5年未受到刑事处罚,最近3年未因违法经营受到行政处罚,不存在因涉嫌违法经营、犯罪正在被调查的情形

Ⅳ.最近3年在税务、工商、金融等行政管理机关,以及自律组织、商业银行等机构无不良诚信记录

A.Ⅱ、Ⅲ、Ⅳ

B.Ⅰ、Ⅱ、Ⅲ、Ⅳ

C.Ⅰ、Ⅱ、Ⅳ

D.Ⅰ、Ⅲ、Ⅳ

题型:选择题

Normally, increases in the price of a product decrease its sales except when the price increase accompanies an improvement in the product. Wine is unusual, however. Often increases in the price of a particular producer’s wine will result in increased sales, even when the wine itself is unchanged.
Which of the following, if true, does most to explain the anomaly described above

A.The retail wine market is characterized by an extremely wide range of competing products.

B.Many consumers make decisions about which wines to purchase on the basis of reviews of wine published in books and periodicals.

C.Consumers selecting wine in a store often use the price charged as their main guide to the wine’s quality.

D.Wine retailers and producers can generally increase the sales of a particular wine temporarily by introducing a price discount.

E.(E) Consumers who purchase wine regularly generally have p opinions about which wines they prefer.

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