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问题 选择题

常温下能用铝制容器盛放的是（　　）

A．浓盐酸

B．稀硝酸

C．稀硫酸

D．浓硝酸

答案

A、盐酸是弱氧化性的酸，能和铝反应生成氢气，不能用铝制品容器盛放，故A错误；

B、稀硝酸是强氧化性的酸，能和铝反应，不能用铝制品容器盛放，故B错误；

C、稀硫酸有弱氧化性，能和铝反应生成氢气，不能用铝制品容器盛放，故C错误；

D、铝在浓硝酸中发生钝化现象，故铝制品容器可以盛放浓硝酸，故D正确．

故选D．

单项选择题 A1型题

一阑尾炎穿孔病弥漫性腹膜炎患者，急诊手术后与右下腹放置烟卷式引流条一根，下列处理措施中哪项正确（）。

A.放置1~2天后即可拔除

B.每次换药时旋转拔出约1~2cm，术后1~2天即可拔除

C.每次换药时旋转拔出约1~2cm，术后3~5天即可拔除

D.视引流情况，至术后6~7天方可拔除

E.应术后一周方可拔除
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单项选择题

A total of 4.6 million digital televisions have been sold, and the sales of HDTV sets have quadrupled since last year. Consumers have bought HDTVs to play their DVDs and to have clearer pictures and wide screens. Only a small percentage of the people who have purchased HDTVs, however, have actually hooked their TVs up to receive high-definition television digital signals. Perhaps television viewers are having trouble keeping up with the changes in technology. Even the manufacturers of HDTVs, like Mitsubishi, Thomson Multimedia, Sony, and Samsung seem to have a tough time learning how to make their sets work with the various digital TV formats because little standardization has been required or implemented in the industry.

Some of the HDTVs weigh over 200 lbs., and a variety of retailers offer a delivery service to the buyer’s home to help install the heavy sets. This is known as a white-glove service and usually comes with an extra fee. After HDTV purchasers get their sets home and hook them up, they will still need to work to get the digital signals to their systems. Most of the industry’s cable providers do not yet offer high~definition programing, and only about 15% of commercial television stations have switched over to even the lowest improved digital pictures. Worse yet, viewers may need to install antenna before they can even get the digital signals to their new HDTV sets. Another frustration for home-theater seekers is that the current HDTV sets allow owners only to watch high-definition programs, not to record them.

"Hook up" as in "hooked their TVs up" underlined in Paragraph 1 most probably means to ().

A. have a hood over the TV

B. be connected to

C. relate oneself to

D. keep contact with
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