以下哪些是CDMA20001xEV-DO空中接口的关键技术（）

A．ABC分类法

B．条形码库存控制数据收集

C．批号跟踪

D．以上答案都可以

A．全程监控服务工作和客舱安全，确保国家财产和旅客的安全。

B．隶属机长领导。

C．维护公司利益，有权处理机上服务及客舱安全方面的各种事宜。

D．应急情况下负责广播。

A．此处是飞机壁板最厚处

B．此处是乘务员在客舱中观察发动机状况的最佳位置

C．此处是观察机翼是否结冰的最佳位置

D．此处是观察飞机前缘缝翼和后缘襟翼放下时状况的最佳位置

A.12mm

B.35mm

C.510mm

D.1015mm

A．大雁

B．北极燕鸥

C．旅鼠

A．考拉

B．胆熊

C．鸸鹋

A.有利

B.一般

C.不利

D.危险

Do you know how to study better and make your study more effective(有效的)?We all know that Chinese students usually study very hard for long().This is very good, but it doesn’t () a lot, for an effective student must have enough sleep, enough food and enough rest and exercise.Every day you need to go out for a walk or visit some friends or some nice places.It’s good for your study.

When you return () your studies, your mind will be refreshed(清醒)and you’ll learn more ()study better.Psychologists(心理学家) () that learning takes place this way.Here take English learning () an example.First you make a lot of progress and feel happy.Then your language study seems ()the same.So you will think you’re learning ()and you may give up.This can last for days or even weeks, yet you needn’t give up.At some point your language study will again take another big ().You’ll see that you really have been learning all along.If you get enough sleep, food, rest and exercise, studying English can be very effective and () .Don’t give up along the way.Learn slowly and you’re sure to get a good result.

(1)A.days

B.time

C.hours

D.weeks

(2)A.help

B.give

C.make

D.take

(3)A.after

B.for

C.at

D.to

(4)A.yet

B.and

C.or

D.but

(5)A.have found

B.have taught

C.told

D.said

(6)A.with

B.for

C.as

D.to

(7)A.to have

B.to make

C.to take

D.to stay

(8)A.something

B.anything

C.nothing

D.everything

(9)A.work

B.jump

C.walk

D.result

(10)A.hard

B.common

C.interesting

D.possible