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【单选题】
采用2DPSK系统是因为( )
A.
克服 2PSK中的“倒 π”现象
B.
2PSK 不容易实现
C.
2PSK误码率高
D.
2PSK 传输速率太低
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【单选题】关于佛罗伦萨画派,下列说法不正确的是()。
A.
意大利文艺复兴时代形成的美术流派
B.
马萨乔是该派的代表人物
C.
起源于意大利威尼斯
D.
侧重表现宗教题材
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【简答题】D Antarctica is the southernmost place on Earth, and it is larger than the United Sates and 95% of it is covered with ice. The ice is 5 kilometers thick at places and it never melts. At least that is ...
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【单选题】Though I failed in the exam last term，my teacher gave me an important _________That
A.
1． Though I failed in the exam last term，my teacher gave me an important _________That was a beautiful smile． A．gift
B.
book
C.
note
D.
letter
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【简答题】The four major regions of the United Sates are___________________ ________ _____________.
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【单选题】The United Sates ranks______ in the export of rice in the world.
A.
the first
B.
the second
C.
the third
D.
the fourth
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【单选题】星型连接的对称三相电源的线电压为380V，则电源的相电压为（）。
A.
380V
B.
220V
C.
200V
D.
180V
查看完整题目与答案
【单选题】_____ is the second largest state of the United Sates in area.
A.
Hawaii
B.
Texas
C.
Alaska
D.
Pennsylvania
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【单选题】In the United Sates, the passport is valid for 10 years for people under 18.
A.
Y
B.
N
C.
NG
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【多选题】用孔板流量计测量某管道中水的流量。已知水的密度为1000kg/m^3，粘度为0.001Pas，管道内径为0.045m，孔板的孔径为0.035m。水银压差计的读数为0.1m。下列关于孔板流量计的选项，哪些正确？
A.
根据m值等于0.6，查得C0不变时的数值为0.74。故先假设C0等于0.74，后面再校正。
B.
代入流量计算公式，得到体积流量等于0.00354m^3/s。管道的平均流速为2.23m/s
C.
管道Re=1.0×10^5。查得C0等于0.75
D.
由于C0的相对误差约为1%，如果做严格计算，需要重新以0.75计算，如果认可这一相对误差，可以认为假设正确。
查看完整题目与答案
【简答题】For Chinese wanting to work as nurses in the United Sates, the arrival of the test of the Commission on Graduates of Foreign Nursing Schools (CGFNS) may be a welcome move. The CGFNS has a certificatio...
查看完整题目与答案
相关题目：
【单选题】关于佛罗伦萨画派,下列说法不正确的是()。
A.
意大利文艺复兴时代形成的美术流派
B.
马萨乔是该派的代表人物
C.
起源于意大利威尼斯
D.
侧重表现宗教题材
查看完整题目与答案
【简答题】D Antarctica is the southernmost place on Earth, and it is larger than the United Sates and 95% of it is covered with ice. The ice is 5 kilometers thick at places and it never melts. At least that is ...
查看完整题目与答案
【单选题】Though I failed in the exam last term，my teacher gave me an important _________That
A.
1． Though I failed in the exam last term，my teacher gave me an important _________That was a beautiful smile． A．gift
B.
book
C.
note
D.
letter
查看完整题目与答案
【简答题】The four major regions of the United Sates are___________________ ________ _____________.
查看完整题目与答案
【单选题】The United Sates ranks______ in the export of rice in the world.
A.
the first
B.
the second
C.
the third
D.
the fourth
查看完整题目与答案
【单选题】星型连接的对称三相电源的线电压为380V，则电源的相电压为（）。
A.
380V
B.
220V
C.
200V
D.
180V
查看完整题目与答案
【单选题】_____ is the second largest state of the United Sates in area.
A.
Hawaii
B.
Texas
C.
Alaska
D.
Pennsylvania
查看完整题目与答案
【单选题】In the United Sates, the passport is valid for 10 years for people under 18.
A.
Y
B.
N
C.
NG
查看完整题目与答案
【多选题】用孔板流量计测量某管道中水的流量。已知水的密度为1000kg/m^3，粘度为0.001Pas，管道内径为0.045m，孔板的孔径为0.035m。水银压差计的读数为0.1m。下列关于孔板流量计的选项，哪些正确？
A.
根据m值等于0.6，查得C0不变时的数值为0.74。故先假设C0等于0.74，后面再校正。
B.
代入流量计算公式，得到体积流量等于0.00354m^3/s。管道的平均流速为2.23m/s
C.
管道Re=1.0×10^5。查得C0等于0.75
D.
由于C0的相对误差约为1%，如果做严格计算，需要重新以0.75计算，如果认可这一相对误差，可以认为假设正确。
查看完整题目与答案
【简答题】For Chinese wanting to work as nurses in the United Sates, the arrival of the test of the Commission on Graduates of Foreign Nursing Schools (CGFNS) may be a welcome move. The CGFNS has a certificatio...
查看完整题目与答案