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【单选题】
设随机变量X服从参数为λ(λ＞0)的泊松分布，D 2 (X)/E(X)=( )．A.
1
B.
C.
λ
D.
λ 2
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皮皮学刷刷变学霸
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【简答题】A．FOREIGN KEY B．PRIMARY KEY C．FOREIGN KEY (Sno) REFERENCES S D．FOREIGN KEY (Pno) PEFERENCES P
【单选题】Foreign outsourcing is
A.
an example of foreign direct investment.
B.
an example of internalization.
C.
the transfer of operations to foreign contractors.
D.
the substitution of immigration for foreign direct investment.
E.
currently illegal in the U.S.
【单选题】关于仿制图章去水印的说法以下错误的是()
A.
采样点即为复制的起始点
B.
不同的笔刷硬度不会影响绘制区域的边缘融合效果
C.
使用防止图章工具时按住 Alt 键进行选择
D.
不同的笔刷直径会影响绘制的范围
【单选题】听力原文：Is check ok? (A) Yes, the condition of this machine is very good. (B) Yes, we should check if everything is Ok. (C) Yes, you can use it. (23)
A.
B.
【单选题】Foreign outsourcing is
A.
the transfer of operations to foreign contractors.
B.
an example of internalization.
C.
an example of foreign direct investment.
D.
currently illegal in the U.S.
E.
the substitution of immigration for foreign direct investment.
【多选题】What are the criteria for good summary writing?
A.
Being complete and concise.
B.
Being objective.
C.
Including many details.
D.
Paraphrased in one's own words.
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