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【单选题】
假设有十只同种电器元件,其中有两只不合格品.装配仪器时,从这批元件中一只,如是不合格 品,则扔掉重新一只;如仍是不合格品,则扔掉再取一只,试求在取到合格品之前,已取出的不 合格品只数的数学期望.A.
2/9
B.
4/5
C.
3/8
D.
2/7
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【单选题】Crossing Wesleyan University's campus usually requires walking over colorful messages chalked on the ground. They can be as innocent as meeting announcements, but in a growing number of cases the lang...
A.
Pieces of chalk are scattered everywhere on the ground.
B.
There are some meeting announcements on the billboard.
C.
All kinds of messages are written on the paths.
D.
Some people are shocked by the meeting announcements.
【简答题】It’s a colorful, colorful world painted so ___________
【简答题】java中用关键字 指明继承关系、用关键字 指明接口实现。
【单选题】Crossing Wesleyan University's campus usually requires walking over colorful messages chalked on the ground. They can be as innocent as meeting announcements, but in a growing number of cases the lang...
A.
Pieces of jokes are written in almost every WC.
B.
There are some meeting announcements on the billboard.
C.
All kinds of messages are written on the paths.
D.
Some people are shocked by the meeting announcements.
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