The Internet as it is set up now opera...

单项选择题The Internet as it is set up now operates at three levels. The first is the servers that store data and content for use by customers. Google and other large companies keep massive server farms. These are well-protected from outside programmers by sophisticated software, but clearly that does not always work. The protection devices may fail more and more often as hackers get more skillful.
What are the servers in the Internet business used for

A. The storage of data and content for use by customers.
B. The transmission of data and content for use by customers.
C. The receiving of data and content from various websites.
D. The programming complicated softwar

点击查看答案

你可能感兴趣的试题

1.单项选择题Google’s Gmail system, which serves millions of customers around the world, shut down yesterday. The problem may hurt its efforts to market applications which include e—mail to businesses. Google prides itself on the reliability of its software, at least according to its marketing pitch. It is not clear why Google had the problem. It keeps thousands of servers. Some of those may have developed trouble or some outside programmer, a hackea may have sent a bug into the system to make it collapse.
What happened to Google yesterday

A. It lost millions of customers.
B. Its Gmail system collapsed.
C. Its market application program failed.
D. Its servers were destroyed by hackers.

点击查看答案

2.单项选择题Albert Einstein, whose theories on space time and matter helped unravel(解开) the secrets of the atom and of the universe, was chosen as "Person of the Century" by Time Magazine on Sunday.
A man whose very name is synonymous with scientific genius, Einstein has come to represent more than any other person the flowering of the 20[^th] century scientific thought that set the stage for the age of technology.
"The world has changed far more in the past 100 years than in any other century in history. The reason is not political or economic, but technological-technologies that flowed directly from advances in basic science," wrote theoretical physicist Stephen Hawking in a Time essay explaining Einstein’s significance. "Clearly no scientist better represents those advances than Albert Einstein."
Time chose as runner-up (第二名) President Franklin Roosevelt to represent the triumph of freedom and democracy over fascism, and Mahatma Gandhi as an icon (象征) for a century when civil and human rights became crucial factors in global politics.
Who was chosen as top "Person of the Century" by Time magazine last week

A. Franklin Roosevelt.
B. Mahatma Gandhi.
C. Thomas Edison.
D. Albert Einstein.

点击查看答案

3.单项选择题Twitter, the micro-blogging service used by tens of millions of people, went off-line last month. It blamed the trouble on a malicious programmer in Russia who was trying to shut down the account of a user in neighboring Georgi

a. It is astonishing the local actions of a small number of programmers can bring an entire Internet service to its knees, but that appears to have been the case.
Who was responsible for the collapse of TwitterA. All its users.B. A malicious programmer in Russia.C. A small number of programmers.D. A user in neighboring Georgia,

点击查看答案

4.单项选择题The absence of Y2K induced problems has been remarkable. There were no falling planes, no exploding power stations, no rogue missiles. Those horrors were always the stuff of myth. But so sparse were tales of disaster that journalists were driven to reporting on malfunctions in the breath-testing’ machines used on drunken motorists by the Hong Kong police. More problems may emerge in the coming weeks. Overall, though, Y2K has turned out to be Y20K:
One partial explanation is that the huge effort lavished(浪费) on bug-squashing has worked. The United States, according to a Commerce Department estimate, spent about 100 billion on the problem; the rest of the world probably spent about the same again. Those numbers are far smaller than some of the more exotic figures trailed a few years ago, but they are still substantial. Yet even the countries that had begun work late and done little-southern Europe, Russia, much of Asia-had a trouble free new year. So was the money wasted
According to the author, the amount of money spent on the Y2K problem was

A. too much.
B. not enough.
C. significant.
D. the same as had been expecte

点击查看答案

5.单项选择题"Copy the ways of nature", we were told. Yes, copy Nature—for everything comes directly or indirectly from natural things. Often we have to put our knowledge to work, treating Nature’s materials so as to make them serve our purposes better. We could, certainly, take the skin from a dead animal and at once make a pair of shoes with it; but they wouldn’t be very good shoes. For our purpose it is better first to treat the skin with chemicals that turn it into leather.
Why is it necessary for us to treat Nature’s material

A. An animal’s skin is not really useful to us.
B. Our purposes can be better served.
C. Natural materials are limited.
D. It is difficult to copy natur

点击查看答案

6.单项选择题The other, more publicly acceptable form of geo-engineering would focus on removing carbon from the atmosphere and storing it underground. Known as carbon capture and storage (CCS), this idea is behind today’s experimental clean-power plants, which are attracting lots of research and funding. But clean, coal plants will only reduce future emissions, which does not address the root of the problem. Among all the uncertainties that still surround climate change, one thing has become clear: the scary durability of carbon, which will hang in the air for a thousand years, continuing to warm the planet no matter how drastically future emissions are cut. So there is a growing urgency behind the geo-engineer’s dream: to change the climate by artificial means, either sucking the existing carbon out of the air or cooling the air with solar reflectors.
Why is carbon so scary according to the passage

A. It will contihue to warm the globe for many years.
B. It cannot be easily captured and stored.
C. Its emission will increase in the coming years.
D. It cannot be reflected back into the spac

点击查看答案

7.单项选择题Until recently, the industry has had little guidance in how to proceed with development without harming wildlife. Regulations are mostly imposed by states or local authorities, whose patchwork guidelines vary from stringent to lax. The Wind Turbine Guidelines Advisory Committee, established in 2007 under the U. S. Fish and Wildlife Service, is proposing federal recommendations to reduce wind development’s effect on wildlife. Composed of wind-industry members, wildlife officials, and federal authorities, the committee will present the recommendations to the secretary of the interior for review in October. The recommendations are voluntary, but according to David Stout of the U. S. Fish and Wildlife Service, the guidelines will be" unprecedented in terms of companies agreeing to hold themselves to a higher standard."
The Wind Turbine Guidelines Advisory Committee is composed of all the following EXCEPT

A. wind-industry members.
B. wildlife officials.
C. federal authorities.
D. David Stout.

点击查看答案

8.单项选择题Cigarettes and mental illness have always tend to go together. An estimated 1.25 billionpeople smoke worldwide. Yet people who are depressed or anxious are twice as likely to smoke, and up to 88 per cent of those with psychotic disorders such as schizophrenia are smokers. A recent American survey concluded that around half of all cigarettes bum in the fingers of those with mental illness.
Recent American survey showed that.

A. there are 1.25 billion smokers worldwide.
B. 88% of people with psychotic disorders are smokers.
C. about 625 million smokers have mental problems.
D. 2.5 billion people have mental problems worldwid

点击查看答案

9.单项选择题The mathematical model recommended by Britain’s National Radiological Protection Board (NRPB) predicted that the screening programme would cause 36 cancers per 100,000 women, 18 of them fatal. The model preferred by the UN Scientific Committee on the Effects of Atomic Radiation led to a lower figure of 20 cancers.
The researchers argue that the level of radiation-induced cancers is "not very significant" compared to the far larger number of cancers that are discovered and treated. The Valencia programme, they say, detects between 300 and 450 cases of breast cancer in every 100,000 women screened.
The model recommended by the UN Scientific Committee on the Effects of Atomic Radiation would probably cause ______ cancers in 100,000 women screened.

A. 300
B. 450
C. 36
D. 20

点击查看答案

10.单项选择题A municipal management plan for storm-water runoff is mandated by the Clean Water Act. Early this year, Urban Stormwater Management in the United States, a report commissioned by the Environmental Protection Agency (EPA), recommended a number of ways to manage runoff, including using structural devices, like the kind AbTech produces. Rink is hoping that his merchandise appeals to budget-strapped municipalities. "Compared with building new storm-water treatment plants or upgrading already existing facilities to handle runoff pollution, which would cost in the millions of dollars, our products are very affordable," he says. The federal stimulus bill could make them even more so.
AbTech products are

A. structural devices.
B. the best solution to run off.
C. appealing to budget-strapped municipalities.
D. costly.

点击查看答案

延伸阅读

你可能感兴趣的试题