皮皮学，免费搜题
登录
搜题
【单选题】
已知总体X的分布为P{X = i} = ¼, i = 0, 1, 2, 3, 抽取n = 36的简单随机样本X1, X2, ..., X36, 若Y = X1+X2 +...+ X36, 则E(Y), D(Y)分别为（）.A.
36 ， 54
B.
45 ， 54
C.
54 ， 36
D.
54 ， 45
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【简答题】Food and water have been d________ (分发,配送) among the refugees from the neighboring country.
【简答题】Food and water have been among the refugees from the neighboring country.
【简答题】下图是 LH 型电控汽油喷射系统的组成结构示意图,请写出各编号所代表的组件名称,并说明 LH 型电控汽油喷射系统的工作原理。
【单选题】According to the conversation, the man had bought all the following things online EXCEPT
A.
shoes.
B.
CDs.
C.
camera.
D.
food.
【判断题】Nathaniel Hawthorne's The Scarlet Letter is a novel that reveals Hawthorne's somewhat Puritanism.
A.
正确
B.
错误
【单选题】The passage implies that it is easy to buy’ the following things in the country EXCEPT___
A.
daily necessities
B.
fresh fruits
C.
designer clothes
D.
fresh vegetables
相关题目：
参考解析：
知识点：
题目纠错 0
发布
