以下选项中，不属于OSI参考模型分层的是________。 A．物理层 B．网络接口

（8分）在“验证力的平行四边形定则”的实验中：

(1)某同学在实验过程中的部分实验步骤如下，请你仔细读题并完成有关空缺部分内容：

A．将一根橡皮筋的一端固定在贴有白纸的竖直平整木板上，另一端绑上两根细线。

B．在其中一根细线上挂上5个质量相等的钩码，使橡皮筋拉伸，如图甲所示，记录：

__________           、                        。

C．将步骤B中的钩码取下，然后分别在两根细线上挂上4个和3个质量相等的钩码，用两光滑硬棒B、C使两细线互成角度，如图乙所示，小心调整B、C的位置，使________________，记录________________。

(2)如果“力的平行四边形定则”得到验证，那么图乙中＝________。

Children love playing games. That is a well-known fact. Kids learn how to play games at a very early age, and once they find a game they love, they can play for hours and hours. In fact, games for kids are so popular that there is an entire industry dedicated(献身) to designing and selling them. There seems to be a fun game for kids for every occasion. Christmas and birthday are often celebrated with the family tradition of gifting a new game.

In recent years, however, Internet games and gaming system seem to have taken kids’ world by storm. Online games for kids have quickly become a very popular way to pass the time with small children and teens alike. Online games are a great way to have fun, and they can be quite educational as well. Many online games created for specific age groups encourage grade-appropriate development and educational skills.

Hundreds of websites offer fun and educational games to kids. Many of these sites are created by big names, such as National Geographic, which we can trust. They offer free games that parents know are proper for children. Parents are encouraged to go online and research online games proper for their children’s age before allowing their kids to play these games. Parents want to look for parental controls such as the ability to set or monitor their children’s playtime.

With so many options to choose from, parents and children will find it easy to find fun games and activities on the Internet. And nowadays, being able to use a computer is a very important skill for children to learn, so playing on the computer is definitely both educational and fun. Children are sure to learn new skills about any subject with the right, trusted website.

小题1:The industry of games for kids is fast growing probably because ________.

A．the workers are good at designing

B．children are mostly crazy about games

C．people would like to celebrate birthdays

D．kids don’t like to do their homework小题2:Which of the following is TRUE of National Geographic Games?

A．The news is updated every day.

B．There is a large amount of information.

C．It can help parents to control kids’ playtime.

D．The games on it are good for kids’ mental and physical health.小题3:What’s the author’s attitude to children’s playing computer games?

A．Supportive.

B．Worried.

C．Negative.

D．Doubtful.小题4:What would be the best title for this passage?

A．Traditional games and modern games

B．Computer games harmful to the youth

C．Games for kids changing a lot ever since

D．Internet games with fun and education

ISUP信令为了支撑（ ）

A．管理网

B．ISDN交换

C．同步网

D．计费

施工升降机限速器应隔( )校验一次。

A．半年

B．一年

C．两年

D．不需交验

Zn＋H₂SO₄＝ZnSO₄＋H₂↑的反应属于（）。

A、置换反应

B、分解反应

C、氧化还原反应