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【单选题】
随机选择5所幼儿园小班的480名儿童进行某疫苗的预防效果观察,随访3年结果表明85%的免疫接种者未发生该病,由此可以认为A.
该疫苗预防效果欠佳,仍有15%儿童生病
B.
该疫苗预防有效,因可保护85%儿童生病
C.
不能下结论,因为3年观察时间不够
D.
不能下结论,因为480名儿童样本含量不足
E.
不能下结论,因为未设对照组
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【简答题】TSRS具有什么特点？
【单选题】以住宅为平台,利用综合布线技术、网络通信技术、 安全防范技术、自动控制技术、音视频技术将家居生活有关的设施集成,构建高效的住宅设施与家庭日程事务的管理系统的住宅称为()。
A.
长寿住宅
B.
绿色住宅
C.
智能家居
D.
各选项都不是
【多选题】下列[ ]属于TSRS 具有的特点 ？
A.
TSRS 所有接口均通过以太网连接
B.
TSRS 系统为冗余结构
C.
系统结构简单、合理
D.
系统具有高安全性、高可靠性和易维护、少维修、易扩展的优点
【单选题】. It was _____ his mother came in _____ to prepare his lessons.
A.
not until; did the boy begin
B.
until; that the boy didn’t begin
C.
until; did the boy not begin
D.
not until; that the boy began
【单选题】_____ his father came back from work_____ his homework.
A.
Not until; he did
B.
It wasn't until; when he did
C.
It was until; that he didn't do
D.
It wasn't until; that he did
【简答题】My dad was a fisherman. He worked hard and stayed out until he caught enough ______ to feed the family nearly every day. When the weather was bad he would ______ me to school. An old truck was used i...
【单选题】智能家居是以( ) 为平台,利用综合布线技术、网络通信技术、 安全防范技术、 自动控制技术 、音视频技术将家居生活有关的设施集成,构建高效的住宅设施与家庭日程事务的管理系统
A.
家庭
B.
住宅
C.
楼房
D.
城市
【简答题】TSRS 具有什么特点 ?
【单选题】It was his mother came in to prepare his lessons. [ ]
A.
not until; did the boy begin
B.
until; that the boy began
C.
until; did the boy begin
D.
not until; that the boy began
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