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【单选题】
开关电源的功率可由下式计算: Pin = Pout / η 这里的η是( )A.
估计的开关电源效率
B.
开关电源的效率
C.
开关电源总效率
D.
电源内高频变压器的效率
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【单选题】— Which is ______ river in China? — The Yellow River. [ ]
A.
the second long
B.
two longest
C.
the second longest
D.
two long
【简答题】A．She is likely to be employed soon. B．She is no[sure of second interview. C．She will see the general manager again. D．She has been employed by the company.
【单选题】下列关于等高线的叙述，( )项为不妥。
A.
在同一张地形图上，等高距是相同的
B.
等高线间距与地面坡度成正比
C.
相邻两条等高线之间的高差是等高距
D.
相邻两条等高线之间的水平距离叫等高线间距
【单选题】We learn from the second paragraph that ______ .
A.
In the Kingdom of the Seals tells the seal hunter not to wound a seal
B.
In the Kingdom of the Seals tells a story about a seal hunter
C.
The seal hunter did not want to kill the seal
D.
The seal can always swim with a knife in its back
【简答题】7j.mp3: Second, a sense of cr, a radical break in culture, an overturning (4wds)_____ ____ ____ _____ that goes with a sense that civilization itself is being overturned.
【单选题】'The second floor' in America is the same as '______' in England.
A.
the first floor
B.
the second floor
C.
the ground floor
【多选题】下列关于等高线的叙述中( )项为妥。
A.
在同一张地形图上，等高距是相同的
B.
等高线间距与地面坡度成正比
C.
相邻两条等高线之间的高差是等高距
D.
相邻两条等高线之间的水平距离叫等高线间距
【单选题】Excel 2010不仅具备了快速编辑报表的能力,同时还具有强大的数据处理功能,其中“()”功能能够将筛选、排序和分类汇总等操作依次完成,并生成汇总表格。
A.
自动筛选
B.
高级筛选
C.
数据透视表
D.
合并计算
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