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【简答题】
一般情况下,视图是一张虚拟表,是通过______来定义视图。
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皮皮学刷刷变学霸
举一反三
【简答题】听音填空，完成对话。 Kim: Hello, what's your name? Li Ming: My name is Li Ming. Kim: ____________ ____________ are you? Li Ming: I'm ____________. Kim: ____________ are you ____________? Li Ming: I'm __________...
【简答题】设发送端符号为X:x1=0,x2=1;接收端符号为Y:y1=0,y2=1;已知P(x1)= P(x2)=0.5;
P(y1|x1)=P(y2|x2)=0.9, P(y2|x1)=P(y1|x2)=0.1;则下列计算与判断正确的是( )。 (10.0分)A. P(y1)=P(y2)=0.5 B. P(x1,y1)=P(x2,y2)=0.9*0.5=0.45； P(x1,y2)=P(x2,...
【简答题】However, the seller also has to Procure insurance against the buyer’s risk of loss or damage to the goods during the carriage．Consequently，the seller contracts for insurance and pays the insurance pre...
【简答题】补全对话。 Li Ming: _________. My name is Li Ming. What's your name? Jenny: My __________ is Jenny.
【单选题】DISSEMBLE:
A.
behave honestly
B.
place collectively
C.
work normally
D.
procure easily
E.
present immediately
【单选题】It is ________ room. They like it very much. [ ]
A.
Li Lei's and Li Ming's
B.
Li Lei's and Li Ming
C.
Li Lei and Li Ming's
D.
Li Lei and Li Ming
【多选题】设发送端符号为X:x1=0,x2=1;接收端符号为Y:y1=0,y2=1;已知P(x1)=0.55, P(x2)=0.45; P(y1|x1)=P(y2|x2)=0.9, P(y2|x1)=P(y1|x2)=0.1;则下列计算与判断正确的是( )。
A.
P(y1)=P(x1)P(y1|x1)+P(x2)P(y1|x2)=0.55*0.9+0.45*0.1=0.54
B.
P(y2)=P(x1)P(y2|x1)+P(x2)P(y2|x2)=0.55*0.1+0.45*0.9=0.46
C.
P(x1,y1)=P(x1)P(y1|x1)=0.55*0.9=0.495； P(x1|y1)=P(x1,y1)/P(y1)=0.495/0.54=0.917
D.
P(x1,y2)=P(x1)P(y2|x1)=0.55*0.1=0.055; P(x1|y2)=P(x1,y2)/P(y2)=0.055/0.46=0.12
E.
P(x2,y1)=P(x2)P(y1|x2)=0.45*0.1=0.045; P(x2|y1)=P(x2,y1)/P(y1)=0.045/0.54=0.083
F.
P(x2,y2)=P(x2)P(y2|x2)=0.45*0.9=0.405; P(x2|y2)=P(x2,y2)/P(y2)=0.405/0.46=0.88
G.
P(x2|y1)≠P(x1|y2)，P(x1|y1)≠P(x2|y2)，所以该信道不是对称信道。
【单选题】采用约当产量法进行原材料费用的分配,在产品完工程度可能按工时定额计算的条件是( )。
A.
原材料在生产开始时一次投入
B.
原材料陆续投入并与加工进度基本一致
C.
原材料陆续投入但与加工进度不一致
D.
原材料分工序一次投入
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