据报道,科学家已成功合成了少量新物质N4,有关N4的说法正确的是( ) A.N4

题型:选择题

问题:

据报道,科学家已成功合成了少量新物质N4,有关N4的说法正确的是(  )

A.N4是两个N2分子构成的

B.N4这种物质是由四个氮原子构成的

C.N4是氮的单质

D.相同质量的N4和N2所含原子个数比为1:2

考点:构成物质的微粒(分子、原子、离子)单质和化合物
题型:选择题

外感温燥,治宜选用()

A.桑杏汤

B.清燥救肺汤

C.杏苏散

D.麦门冬汤

E.养阴清肺汤

题型:选择题

对于因船舶碰撞或者其他海事损害事故请求损害赔偿提起的诉讼,下列哪些法院享有管辖权

A.碰撞发生地法院

B.碰撞船舶最先到达地法院

C.加害船舶被扣留地或者被告住所地法院

D.船籍港所在地法院

题型:选择题

当上、下层水平气压梯度相同时,上层水平气压梯度力应比下层的()。

A.小

B.大

C.相同

题型:选择题

Many people are surprised when they find the Internet(因特网)was set up in the 1960s. At that time, computers were large and expensive. Computer networks(网络) didn’t work well. If one computer in the network broke down, then the whole network stopped. So a new network system (系统) had to be set up. It should be good enough to be used by many different computers. If a part of the network was not working, information could be sent through another part. In this way computer network system would keep on working all the time.
At first the Internet was only used by the government, but in the early 1970s,universities(大学) ,hospitals and banks were allowed(允许) to use it too. However, computers were still very expensive and the Internet was difficult to use. By the start of the 1990s, computers became cheaper and easier to use.
Today it is easy to get on-line(上网) and it is said that millions of people use the Internet every day. Sending e-mail is more and more popular among students.
The Internet has now become one of the most important parts of people’s life.

The word" information" may probably mean

A. letter


B. message

C. number

题型:选择题

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