(66) is a channel’ s capacity which direc_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题单项选择题

(66) is a channel’ s capacity which directly reflects the data transfer rate of the channel. (67) functions in a NetWare network which is used to define addressing schemes. (68) is a network layer device that suports multiple LAN interfaces and segments LANs into smaller collision and broadcast domains. (69) ．is the popular LAN develped under the direction of the IEEE 802.3. (70) is a device which enables digital microcomputers to communicate across analog telephone lines.

A. The repeaterB. The hub
C. The bridge D. The router

答案

参考答案：D

选择题

“科学思维应该天马行空，科学研究必须脚踏实地”。最能概括这一观点的是[ ]

A、既要有创新意识，又要求真务实

B、不唯上，不唯书，只唯实

C、既要尊重权威，又要学习书本知识

D、要坚持辩证法的革命批判精神

填空题

World Water Shortage

A new study warns that about thirty percent of the world’s people may not have enough water by the year 2025.
A private American organization called (1) Action International did the new study. It says (2) than three-hundred-thirty-five-million people (3) enough water now. The people live in twenty-eight (4) . Most of the countries are in Africa or the (5) East.
P-A-I researcher Robert Engelman says (6) the year 2025, about three-thousand-million people (7) lack water. At least 18 more countries are (8) to have severe water problems. The demand (9) water keeps increasing. Yet the amount of water on Earth (10) the same.
Mr. Engelman says the population in countries that lack water is (11) faster than in other parts of the world. He says (12) growth in these countries will continue to (13) .
The report says lack of water in the future may (14) in several problems. It may increase health (15) . Lack of water often means drinking (16) not safe. Mr. Engelman says there are problems (17) over the world because of diseases, such as cholera, (18) are carried in water. Lack of water may also result (19) more international conflict. Countries may have to (20) for water in the future. Some countries now get sixty percent of their fresh water from other countries. This is true of Egypt, the Netherlands, Cambodia, Syria, Sudan, and Iraq. And the report says lack of water would affect the ability of developing to improve their economies. This is because new industries often need a large amount of water when they are beginning.