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问题 多项选择题

下列哪些情况可装设备用电源或备用设备的自动投入装置？（）

A.由双电源供电的变配电所，其中一个电源经常断开作为备用

B.变配电所内有两台所用变压器

C.变配电所内有互为备用的母线段

D.变配电所内有备用变压器

答案

参考答案：A, B, C, D

单项选择题

The fact that most Americans live in urban areas does not mean that they reside in the center of large cities. In fact, more Americans live in the suburbs of large metropolitan areas than in the cities themselves.
The Bureau of the Census regards any area with more than 2,500 people as an urban area, and does not consider boundaries of cities and suburbs.
According to the Bureau, the political boundaries are less significant than the social and economic relationships and the transportation and communication systems that integrate a locale. The term used by the Bureau for an integrated metropolis is an MSA, which stands for Metropolitan Statistical Area. In general, an MSA is any area that contains a city and its surrounding suburbs and has a total population of 50,000 or more.
At the present time, the Bureau reports more than 280 MSAs, which together account for 75 percent of the US population. In addition, the Bureau recognizes 18 megapolises, that is, continuous adjacent metropolitan areas. One of the most obvious megapolises includes a chain of hundreds of cities and suburbs across 10 states on the East Coast from Massachusetts to Virginia, including Boston, New York, and Washington, D.C. In the Eastern Corridor, as it is called, a population of 45 million inhabitants is concentrated. Another megapolis that is growing rapidly is the California coast from San Francisco through Los Angeles to San Diego.

The underlined word "reside" in Paragraph 1 is closest in meaning to ______.

A．fill

B．decide

C．occupy

D．live
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填空题

公安信息可按管理层级划分两大类，分别基础信息和（）。
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