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小明房间新添了一台变频空调,部分参数如下表所示。变频空调工作时,可自动调节制冷功率,当室温和空调的设定温度相差较大时,变频空调一开机,即以最大功率工作,使室温迅速达到设定温度;当室温达到设定温度后,空调的制冷功率随之减小,以维持室温基本不变。夏天的一晚,空调开机后以最大制冷功率工作0.5h,使室温降至设定温度;然后,空调又以某一恒定的功率工作了2.5h,全过程空调消耗的电能为1.8kW·h。求

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阅读下面四篇短文,从各题所给的A、B、C、D四个选项中选出最佳选项。

    If you meet a British person in the street, it is very likely that he or she will apologize whether it is his or her fault (过错) or not.

    It seems that Britain is becoming a nation where everyone is saying sorry. Almost each person says sorry about eight times each day—and one in eight people apologize as many as 20 times a day.

    As you may have seen, the British apologize more often than members of other cultures. A research shows that in many cases, people's love of saying sorry in Britain goes a little further than it does for Americans. For example, about 15 British people would say ”sorry” while only 10 from the US would do this if they sneezed, if they corrected someone's mistake of if someone knocked into them.

    In the old days, “sorry” was used to express regret and sadness for having done something wrong. But now British people use the expression as a way of showing good manners. For example, they might say “sorry” instead of “excuse me”, “pardon”, “what” or “whatever”.

    People in Britain also use sorry when they share the same feeling with others—so they might say “sorry about the rain”.

    However, British people's use of “sorry” may make things very confusing (迷惑不清) and difficult for foreigners who are not familiar with their ways. But actually, people in Britain pay much attention to the feelings of others. This is the very reason why they apologize every day.