电子商务网站的软件由以下()构成。A、操作系统 B、服务器软件 C、数据库 D、软件

题型:多项选择题

问题:

电子商务网站的软件由以下()构成。

A、操作系统

B、服务器软件

C、数据库

D、软件开发工具

E、硬盘

考点:经济学电子商务电子商务题库
题型:多项选择题

What if we could replace oil with a fuel which produced no pollution and which everybody had equal access to? The good news is that we can. In fact, we are swimming in it--- literally.

Hydrogen is one of the building blocks of the universe. Our own sun is basically a big, dense cloud of the stuff. And hydrogen can be used to create electricity for power, heat and light.

The problem is that hydrogen is everywhere and nowhere at the same time. It does not exist as a material on its own, but is always part of something else. So it has to be separated before it can be used.

Most commercial hydrogen in use now is created from natural gas. As oil will start to run out in around the year 2030, it makes sense to produce as much hydrogen as possible as soon as we can. But natural gas supplies will also begin to run out soon after. Another source is needed.

Researchers are now using electricity to make water into hydrogen. Companies are working on the problem in their own areas. The first commercial hydrogen “fuel cells” for computers and mobile phones have already come on to the market. Auto companies have also invested over US $2 billion in the production of hydrogen fuelled cars.

The nations of a hydrogen fuelled planet would not fight over energy recourses. There would be a great reduction in pollution. The only by-product of creating hydrogen is pure drinking water--- something that is very scarce in many parts of the world. But that is not where the good news ends. Once the costs of producing hydrogen have been brought down, it will possibly provide power for a third of the Earth’s population that has no electricity.

And electricity creates wealth. In South Africa over the last decade there has been a large programme of electrification. Thanks to the programme, people do not have to spend their days looking firewood to burn for heat. And with electric light, they can work long into the night.

Some scientists see radical changes in the way the human race co-operates. Hydrogen creates electricity, and is also created by it. With dual use fuel cells, everyone who consumes energy could also produce it. Late at night, a man drives home in London and connects his car into the “world-wide hydrogen web,” which it supplies with electricity. A few hours later, a man in Beijing uses that electricity to power the hydrogen cell in his car. Hydrogen could be the first democratic energy source.

Like all dreams of the future, it seems very far away. But the threat of war and terrorism in the Middle East has made governments and businesses more aware of the need to end oil dependency and spend more time and money on hydrogen resource. So maybe the threat of war is not a completely bad thing for the future of the human race.

小题1:What does the underlined word “it” in the last but one paragraph refer to?

A.wealth

B.hydrogen

C.electricity

D.fuel小题2:What is the problem with using hydrogen as energy?

A.It has by-products.

B.It has to be separated from other materials.

C.It will make energy too cheap.

D.It is too far away from us.小题3:Why does the author give the example in the last but one paragraph ?

A.To tell us that we produce energy while using hydrogen power.

B.To tell us that hydrogen power does not produce pollution.

C.To show hydrogen power can stop war.

D.To show hydrogen power is cheap.小题4:What is the author’s attitude about the future?

A.skeptical

B.negative

C.indifferent

D.positive小题5:What is the passage mainly about?

A.war and energy

B.the future of hydrogen as an energy resource

C.the disadvantages of oil

D.How to end war

题型:多项选择题

病历摘要:患者男性,38岁,右眼前有黑影漂动十天伴下方视物不清七天,不伴有红肿及眼痛症状,否认有眼外伤史,但有高度近视史约十年,家族中无类似病史。

就患者目前病情,采用下列哪种方法更合适?()

A.玻璃体切割联合眼内注气

B.玻璃体切割联合硅油填充

C.单纯玻璃体切割术

D.巩膜冷凝、放液联合外加压术

E.单纯外放液术

F.巩膜电凝联合外放液术

G.巩膜冷凝、放液联合环扎术

H.眼内注气术

题型:多项选择题

男性,48岁。劳力后心悸、气短12年,反复下肢水肿半年,饮酒史20年300ml/d以上。查体:颈静脉怒张,心界向两侧扩大,心率快,心音低钝,心尖部2/6级SM,三尖瓣区2/6级SM,两肺细小水泡音。心电图:左束支完全性传导阻滞,低电压,ST-T改变。

下列哪项措施非常重要()。

A.运动

B.戒酒

C.戒烟

D.减肥

E.保证睡眠

题型:多项选择题

“黄道吉日”是怎么回事?

题型:多项选择题

过去10年里,和平、发展、合作的时代潮流更加强劲;同时局部冲突和热点问题此起彼伏,影响着世界和平稳定,南北发展不平衡依然突出,环境恶化、粮食安全、能源资源安全等全球性问题受到普遍关注。据此回答下题。

上述材料蕴含的主要信息有()

①当今世界仍然很不安宁②不公正、不合理的国际旧秩序仍然存在

③恐怖主义成为和平与发展问题的主要障碍④求和平、促发展、谋合作成为时代的主旋律

A.②③④

B.①②④

C.①②

D.①④

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