问题
多项选择题
二元二位继电器具有的最显著的特征是（）。
A.频率选择性
B.可靠稳定性
C.相位选择性
D.吸起值电压高
答案
参考答案：A, C
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二元二位继电器具有的最显著的特征是（）。
A.频率选择性
B.可靠稳定性
C.相位选择性
D.吸起值电压高
参考答案：A, C
| "A good newspaper is a nation talking to itself," mused Arthur Miller in 1961. A decade later, two reporters from the Washington Post wrote a series of articles that brought down President Nixon and the status of print journalism soared. At their best, newspapers hold governments and companies to account. They usually set the news agenda for the rest of the media. But in the rich world newspapers are now an endangered species. Of all the old media, newspapers have the most to lose from the Internet. Circulation has been falling in the U. S., Western Europe and Latin America for decades. But in the past few years the web has hastened the decline. In his book The Vanishing Newspaper, Philip Meyer calculates that the first quarter of 2043 will be the moment when newsprint dies in the U. S. as the last exhausted reader tosses aside the last crumpled edition. Newspapers have not yet started to shut down in large numbers, but it is only a matter of time. Over the next few decades half the rich world’s general papers may fold. Jobs are already disappearing. According to the Newspaper Association of America, the number of people employed in the industry fell by 18% between 1990 and 2004. Having ignored reality for years, newspapers are at last doing something. In order to cut costs, they are already spending less on journalism. Many are also trying to attract younger readers by shifting the mix of their stories towards entertainment, lifestyle and subjects that may seem more relevant to people’s daily lives than international affairs and politics are. They are trying to create new businesses on-and offline. And they are investing in free dally papers. So far, this fit of activity looks unlikely to save many of them. Even if it doest, it bodes ill for the public role of the Fourth Estate. Nobody should relish the demise of once-great titles. But the decline of newspapers will not be as harmful to society as some fear. Democracy, remember, has already survived the huge television-led decline in circulation since the 1950s. It has survived as readers have shunned papers and papers have shunned what was in stuffier times thought of as serious news. And it will surely survive the decline to come. The usefulness of the press goes much wider than investigating abuses or even spreading general news; it lies in holding governments to account -- trying them in the court of public opinion. The Internet has expanded this court. Anyone looking for information has never been better equipped. People no longer have to trust a handful of national papers or, worse, their local city paper. In future, some high-quality journalism will be backed by non-profit organizations. Already, a few respected news organizations sustain themselves that way. An elite group of serious newspapers available everywhere online, independent journalism backed by charities, thousands of fired-up bloggers and well-informed citizen journalists: there is every sign that Arthur Miller’s national conversation will be louder than ever. |
The author puts stress on the survival of democracy to show that ______.
A．democracy has great vitality to survive
B．people should not take pleasure in the decline of newspapers
C．the decline of newspapers won’t be so harmful to society
D．democracy might not survive the coming decline of newspapers