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【简答题】
设随机变量 独立, ,则 ;
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皮皮学刷刷变学霸
举一反三
【单选题】下列各项中,属于修订后的《会计档案管理办法》施行日期是( )
A.
2016 年 1 月 1 日
B.
2016 年 3 月 1 日
C.
2016 年 6 月 1 日
D.
2016 年 9 月 1 日
【单选题】By the middle of the 21 st century, the vast majority of the world’s population _____ in cities rather than in the country.
A.
are living
B.
will be living
C.
have lived
D.
will have lived
【单选题】By the middle of the 1920s the farthest corners of the earth explored.
A.
are
B.
were
C.
have been
D.
had been
【单选题】By the middle of the 21st century, the vast majority of the world’s population
A.
other than
B.
more than
C.
better than
D.
rather than
【单选题】By the middle of the 21st century, the vast majority of the world’s population ______ in cities rather than in the country.
A.
are living
B.
will be riving
C.
have lived
D.
will have lived
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