皮皮学，免费搜题
登录
搜题
【单选题】
电源电压为+18V的555定时器,接成施密特触发器,则该触发器的 上限阀值电压U T+ 及下限阀值电压U T- 分别为 ( )A.
+12V ，+6V
B.
+12V ，+12V
C.
+6V ，+6V
D.
+6V ，+12V
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
【单选题】The couple less ______ to each other tend to end up in divorce.
A.
committed
B.
linked
C.
connected
D.
contributed
【单选题】关于离座时的基本要求,下列说法错误的是( )
A.
事先说明。离开座椅时,身边如果有人在座,应该用语言或动作向对方先示意,随后再站起身来;
B.
注意先后。和别人同时离座,要注意起身的先后次序,地位低于对方时,应该稍后离座;地位高于对方时,可以首先离座;双方身份相似时,可以同时起身离座;
C.
起身缓慢。起身离座时,最好动作轻缓,不要“拖泥带水”,尽量不弄响座椅或将椅垫、椅罩掉在地上;
D.
从后面离开;
【单选题】Some hosts don’t want dogs in their homes because _________.
A.
dogs may bite others
B.
their children are allergic to dog’s hair
C.
dogs often make a mess
D.
the sofa and carpet may get stained
【单选题】We' d like to clear up some points ( )with the technical part of the contract.
A.
connected
B.
connect
C.
connecting
D.
being connected
【单选题】Why didn’t the dogs dare to get their food back ?
A.
Because the dogs didn’t know who steals.
B.
Because Cranberry is the leader of the group.
C.
Because the dogs weren’t hungry.
D.
Because Cranberry is a star in the neighborhood.
【单选题】Why does the woman think people can't have dogs in their apartments?
A.
As her host mother doesn't like dogs.
B.
As dogs are really small.
C.
As their apartments are tiny.
D.
As there are too many dogs around the city.
【单选题】Both bus and tree topologies are characterized by the use of multipoint().
A.
medium
B.
connection
C.
token
D.
resource
相关题目：
参考解析：
知识点：
题目纠错 0
发布
