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图4-30表示发电机的励磁回路。为使其中的激励电流迅速达到额定值，可在建立磁场过程中，一方面提高激励电压，即在励磁回路中增加一个电源；另一方面串入一个适当电阻，以便使线圈电流的额定值不发生改变，如图中虚线所不。在合上开关S1建立起额定激励电流后，即司闭合S2，再断开S1，使励磁回路处于正常工作状态。现要求将建立额定磁场所需要的时间缩短 ，问附加电压U s 及电阻R各为多少?
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【判断题】显示和隐藏标尺的快捷键是Ctrl+D
A.
正确
B.
错误
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【判断题】当我们还在大张旗鼓地宣传以学科为中心的时候,世界一流大学已经开始瞄准以学生为中心的本科教学,重视质量、重视人才培养已经成为世界高等教育的共识和趋势。( )
A.
正确
B.
错误
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【单选题】You executed the following commands：   SQL> ALTER SESSION SET OPTIMIZER_USE_PENDING_STATISTICS = false； SQL> EXECUTE DBMS_STATS.SET_TABLE_PREFS（’SH’， ’CUSTOMERS’， ’PUBLISH’，’false’）； SQL> EXECUTE DBMS...
A.
The statistics are stored in the pending statistics table in the data dictionary.
B.
The statistics are treated as the current statistics by the optimizer for all sessions.
C.
The statistics are treated as the current statistics by the optimizer for the current sessions only.
D.
The statistics are temporary and used by the optimizer for all sessions until this session terminates.
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【单选题】You executed the following commands: Which statement is correct regarding the above statistics collection on the SH.CUSTOMERS table in the above session?（）
A.
The statistics are stored in the pending statistics table in the data dictionary.
B.
The statistics are treated as the current statistics by the optimizer for all sessions.
C.
The statistics are treated as the current statistics by the optimizer for the current sessions only.
D.
The statistics are temporary and used by the optimizer for all sessions until this session terminates.
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【单选题】名为“Statistics”的工作表的A4单元格的地址应表示为______。
A.
A4!Statistics    
B.
Statistics/A4
C.
Statistics!A4  
D.
Statistics＼A4
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【单选题】听力原文：W： Mary wants to take statistics this year, but according to the requirements, she has to take the accounting course first. M: She may ask Professor Lee Smith if she could take them simultaneousl...
A.
Professor Smith will help Mary to take the course simultaneously.
B.
Mary will probably postpone taking the course of statistics.
C.
Mary will require taking the accounting course first.
D.
Mary will take the course of Professor Smith.
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【单选题】下列植物为一年生植物的是
A.
千日红
B.
菊花
C.
万年青
D.
月季
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【单选题】显示和隐藏标尺的快捷键是?
A.
Alt+Ctrl+R
B.
Ctrl+R
C.
Ctrl+V
D.
Ctrl+C
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【单选题】显示和隐藏标尺的快捷键是?
A.
Ctrl+R
B.
Shift+Ctrl+R
C.
Ctrl+H
D.
Ctrl+‘
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【判断题】当我们还在大张旗鼓地宣传以学科为中心的时候,世界一流大学已经开始瞄准以学生为中心的本科教学,重视质量、重视人才培养已经成为世界高等教育的共识和趋势。
A.
正确
B.
错误
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相关题目：
【判断题】显示和隐藏标尺的快捷键是Ctrl+D
A.
正确
B.
错误
查看完整题目与答案
【判断题】当我们还在大张旗鼓地宣传以学科为中心的时候,世界一流大学已经开始瞄准以学生为中心的本科教学,重视质量、重视人才培养已经成为世界高等教育的共识和趋势。( )
A.
正确
B.
错误
查看完整题目与答案
【单选题】You executed the following commands：   SQL> ALTER SESSION SET OPTIMIZER_USE_PENDING_STATISTICS = false； SQL> EXECUTE DBMS_STATS.SET_TABLE_PREFS（’SH’， ’CUSTOMERS’， ’PUBLISH’，’false’）； SQL> EXECUTE DBMS...
A.
The statistics are stored in the pending statistics table in the data dictionary.
B.
The statistics are treated as the current statistics by the optimizer for all sessions.
C.
The statistics are treated as the current statistics by the optimizer for the current sessions only.
D.
The statistics are temporary and used by the optimizer for all sessions until this session terminates.
查看完整题目与答案
【单选题】You executed the following commands: Which statement is correct regarding the above statistics collection on the SH.CUSTOMERS table in the above session?（）
A.
The statistics are stored in the pending statistics table in the data dictionary.
B.
The statistics are treated as the current statistics by the optimizer for all sessions.
C.
The statistics are treated as the current statistics by the optimizer for the current sessions only.
D.
The statistics are temporary and used by the optimizer for all sessions until this session terminates.
查看完整题目与答案
【单选题】名为“Statistics”的工作表的A4单元格的地址应表示为______。
A.
A4!Statistics    
B.
Statistics/A4
C.
Statistics!A4  
D.
Statistics＼A4
查看完整题目与答案
【单选题】听力原文：W： Mary wants to take statistics this year, but according to the requirements, she has to take the accounting course first. M: She may ask Professor Lee Smith if she could take them simultaneousl...
A.
Professor Smith will help Mary to take the course simultaneously.
B.
Mary will probably postpone taking the course of statistics.
C.
Mary will require taking the accounting course first.
D.
Mary will take the course of Professor Smith.
查看完整题目与答案
【单选题】下列植物为一年生植物的是
A.
千日红
B.
菊花
C.
万年青
D.
月季
查看完整题目与答案
【单选题】显示和隐藏标尺的快捷键是?
A.
Alt+Ctrl+R
B.
Ctrl+R
C.
Ctrl+V
D.
Ctrl+C
查看完整题目与答案
【单选题】显示和隐藏标尺的快捷键是?
A.
Ctrl+R
B.
Shift+Ctrl+R
C.
Ctrl+H
D.
Ctrl+‘
查看完整题目与答案
【判断题】当我们还在大张旗鼓地宣传以学科为中心的时候,世界一流大学已经开始瞄准以学生为中心的本科教学,重视质量、重视人才培养已经成为世界高等教育的共识和趋势。
A.
正确
B.
错误
查看完整题目与答案