甲从学校乘车回家,途中有3个交通岗,假设在各交通岗遇红灯的事件是相互独立的,并且

题型:填空题

问题:

甲从学校乘车回家,途中有3个交通岗,假设在各交通岗遇红灯的事件是相互独立的,并且概率都是
2
5
,则甲回家途中遇红灯次数的期望为______.
考点:离散型随机变量的期望与方差
题型:填空题

— I am interested in that laptop. It seems to be the latest style.What do you charge for it?

— $8000.

— ________,  but I can't afford it. [ ]

A. It's worth that 

B. It's really nice

C. Please lower the price  

D. That's too dear

题型:填空题

上消化道呕出大量鲜红色血,且不易控制的常见病为()

A.十二指肠球后溃疡出血

B.应激性溃疡出血

C.食管胃底静脉曲张破裂出血

D.胆道出血

E.胃癌出血

题型:填空题

优质的服务价值对比实物价值更容易被抄袭。

题型:填空题

Who has got an English book
A. The man. B. The woman. C. Both.

题型:填空题

被动体位

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