问题 问答题 简答题

现代投影机有哪些类型和选用要求?

答案

参考答案:

(1)根据采用的投影技术分类,现代投影机主要可以分为:

①阴极射线管投影器

②液晶投影器

③数字光处理器投影器

(2)投影机的选用

要根据显示环境来决定投影器的类型——演示室面积、投影器亮度现在一般都选用亮度在1000ANSI流明以上的投影器。投影器亮度选择标准如表1和表2所示。

阅读理解
     A

I am Alice. I like We chat. It is fast, convenient and fashionable. And you can use it for free. It can be used in my mobile phone. It has hold-to-talk voice messaging function. I am a fan of Leehom Wang. Through We chat, Leehom Wang often says something to me. It’s amazing.

I am David. I love Micro blog. I update my Micro blog when I am free. We can share instant(即时的) messages with each other. I often look through Yao Chen’s Micro blog. She has many followers. I make many friends with them. I often write something on my Micro blog, for example, “I’m in blue today. I didn’t pass the exam.” Then many friends comfort me. I share my birthday party, my new phone, my new coat, etc. with my friends. It is fun.

I’m Lily. I don’t like We chat or Micro blog. I don’t believe them. There are so many crimes(愚蠢行为) on We chat. Many people are cheated(欺骗) because they believe in other people they meet on We chat easily. It is not a real world. As to Micro blog, I don’t think it is a good way to make friends. And you should write something no more than 140 words. I like keeping diaries. I don’t want my secrets known by others. I am a low-key(低调的) girl.
小题1:Who loves Micro blog?
A.Alice.B.David.
C.Lily. D.Leehom Wang.
小题2:What does Alice think about We chat?
A.It’s fast and convenient. B.It’s fashionable but slow.
C.It’s safe and useful.D.It’s fun but expensive.
小题3:Why doesn’t Lily believe We chat?
A.Because many people are cheated on We chat easily.
B.Because she doesn’t like to say anything to her friends.
C.Because she doesn’t think it is a good way to make friends.
D.Because she prefers keeping diaries to showing secrets to others.
多项选择题