在不透明的袋中有大小、形状和质地等完全相同的小球,它们分别标有数字-1、-2、1

题型:解答题

问题:

在不透明的袋中有大小、形状和质地等完全相同的小球,它们分别标有数字-1、-2、1、2,从袋中任意摸出一小球(不放回),将袋中的小球搅匀后,再从袋中摸出另一个小球。

(1)请你表示摸出小球上的数字可能出现的所有结果;

(2)若规定:如果摸出的两个小球上的数字都是方程x2-3x+2=0的根,则小明赢,如果摸出的两个小球上的数字都不是方程x2-3x+2=0的根,则小亮赢,你认为这个游戏规则对小明、小亮双方公平吗?请说明理由。

考点:列举法求概率
题型:解答题

阅读理解。

    Many children use the Internet to get useful knowledge and information , and to relax in their free time. But some of them are not using in a good way. Here are some rules to make sure you are safe and have fun on the Inter-net.

    ● Make rules for Internet use with your parents. For example, when you can go online, for how long and what activities you can go online.

    ●  Don't give your password (密码) to anyone else,and never leak out the following information-your real name, home address, age , school, phone  number or other

personal information.

    ● Check with your parents before giving out a credit(信用) card number.

    ● Never send a photo of yourself to someone in e-mail unless your parents say it's OK.

    ● Check with your parents before going into a chat room. Different chat rooms have different rules and attract different kinds of people. You and your parents must

make sure it's a right place for you.

    ● Never agree to meet someone you met on the Internet without  your  parent's  permission (允许) . Never meet anyone you met on line alone.

    ●  Always remember that people online may not be who they say they are. Treat everyone online as strangers.

    ● If something you see or read online makes you uncomfortable,leave the site. Tell a parent or teacher right away.

    ● Treat other people as you'd like to be treated.Never use bad language.

    ● Remember-not everything you read on the Internet is true.

1. If you want a true friend on the Internet, you can_____.   

A. tell the people what your name is

B. meet the people online alone

C. write an e-mail about yourself

D. get your parents' permission

2. It's good for children to _____on the Internet.    

A. give password to others

B. get useful knowledge and information

C. give out a credit card number

D. go into a chat room as they'd like to

3. The underlined phrase "leak out" in the third paragraph may mean“____”.

A.give away    

B.leave out

C.give out    

D.put away

4. If your parents don't agree, never____. 

A. read anything on the Internet

B. relax in your free time

C. have a face-to-face meeting with anyone you met online

D. treat other people as you'd like to be treated

5. This passage is mainly about"__________".  

A.How to Use Computers

B.Surfing on the Internet

C. Information on the Internet

D.Internet Safety Rules

题型:解答题

防排烟系统的金属管道板材应采用咬口连接或铆接,除镀锌钢板及含有复合保护层的钢板外,板厚大于()的可采用焊接。

A.0.75mm

B.1.0mm

C.1.2mm

D.1.5mm

题型:解答题

使用重量法测定环境空气中的降尘时,一般采用()水溶液做收集液进行湿法采样。

题型:解答题

信息法的作用不包括()

A.为国家的信息化发展提供法律上的依据和支持

B.为国家的信息化发展排除障碍

C.建立有利于国家信息化发展的社会秩序

D.只创设新的专门的法律规范,不废止、不修改传统法规中不适应数字化、网络化生存环境的内容

题型:解答题

根据《票据法》的规定,下列各项中属于票据基本当事人的是( )。

A.出票人
B.背书人
C.承兑人
D.保证人

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