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问题 选择题

图中N为北极点，A、B为晨昏线与纬线的交点，C为该纬线上一点。读图完成问题。

小题1:该日C地的日出时间和可能的月份为

A．2时 5月

B．10时 6月

C．2时 11月

D．8时 12月小题2:若A、B所夹劣弧为夜弧，且A点两侧日期不同，为7日和8日，则此时北京时间为

A. 7日18时         B. 7日22时

C. 8日18时         D. 8日22时

答案

小题1:A

小题2:D

题目分析：

小题1:N为北极点，A、B为晨昏线与纬线的交点，则AB弧要么是昼弧，要么是夜弧，若AB弧是昼弧，则该日昼长为60o/15o/h=4h,即C地昼长为4小时，10：00日出，则北极点附近为极夜现象，对应下半年时间，可能为11或12月；若AB弧是夜弧，则该日夜长为60o/15o/h=4h,即C地夜长为4小时，2：00日出，则北极点附近为极昼现象，对应上半年时间，可能为5或6月；综合分析本题选A。

小题2:若A、B所夹劣弧为夜弧，则平分AB弧的经线地方时为0：00，如下图所示。又因为A点两侧日期不同，为7日和8日，则A点所在经线为180度经线，根据自西向东过180度经线减一天，确定7日、8日范围，由图可知150oE地方时为0：00，则此时北京时间即120oE的地方时为7日22时。

点评：本题难度较大，解答本题的关键是：（1）明确同一条纬线圈上的点日出日落时刻相同，昼夜长短相同，正午太阳高度相同。（2）明确日期分界线的判断方法，自西向东过180度经线减一天，自西向东过0时经线加一天。（3）明确北京时间就是120oE的地方时，东八区的区时。

多项选择题

根据肾脏是否发生器质性损害可将急性肾功能衰竭分为（）。

A.肾性ARF

B.肾前性ARF

C.肾后性ARF

D.功能性ARF

E.器质性ARF
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问答题

On Feb. 17, 2009, it could snow all across America. Not outside, but in living rooms, on TV sets. That’s the date when broadcasters will switch to digital transmission, rendering millions of standard analog TVs useless. Consumers can avoid this whiteout, but only if they’re prepared. And there’s the challenge: How to inform the roughly 20 million households relying exclusively on analog sets that pull in their reception for free, through rabbit ears or a rooftop antenna. Analog TVs that receive cable or satellite will not be affected.
Consumers who own these sets don’t necessarily need to know why the federal government is mandating the change (to free up the airwaves for other purposes, such as wireless and public safety communications-though added benefits are better pictures and more channels). But they do need consistent and unbiased information on what to do and they need to be able to act on it. With fewer than 18 months to go, though, 56 percent of viewers with analog sets have never even heard of the switch. The General Accountability Office, the government watchdog, is concerned that with two government agencies involved, "no one is in charge."
The Federal Communications Commission is worried, too. "If we don’t do a better job of planning, we’ll have one of the biggest outrages Congress has ever seen," FCC commissioner Jonathan Adelstein told US senators last month. The options for consumers are fairly straightforward. Starting with the least expensive one, they are:

  • a) buying a converter box using government coupons’
  • b) subscribing to cable or satellite TV services, which will make the transition on their end, or
  • c) buying a digital TV. But sharing this information is anything but simple. Because it has only $ 5 million to get the message out, the government is turning to the private sector for help with public-service announcements and educating consumers in stores. This partnership makes sense, if done right. Certainly, the broadcasting industry wants viewers to keep on watching, However, there’s a danger in their self-interest. Naturally, retailers also want people to buy new digital televisions instead of opting for low-cost converters, and cable and satellite providers want new subscribers. And industry may not have enough of a financial incentive to reach out to certain analog viewing groups, such as the poor or elderly (seniors make up 40 percent of analog households).
    Other serious issues remain. One is whether the converter boxes will be uniformly available in stores. Beginning in January, households should be able to apply to the Commerce Department’s National Telecommunications and Information Administration for up to two $ 40 coupons to offset the costs of converter boxes expected to be priced from $ 50 to $70. But some retailers may not stock the boxes if they don’t have much demand for them.
    And what about recycling analog televisions, of which there are an estimated 70 million More than anything, what’s needed is oversight and coordination of the conversion. Congress should designate one of the two government agencies involved in this project to take the lead, or empower an independent group to oversee the transition.


What is the major topic of this passage Give a list of the serious issues related to the topic.
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