不属于护士排班方法的是（）。 A.每日三班制 B.单人三班制 C.每日二班制 D.多

电子所带电荷量最早是由美国科学家密立根所做的油滴实验测得的．密立根油滴实验的原理如图所示，两块水平放置的平行金属板与电源相连接，使上板带正电，下板带负电，油滴从喷雾器喷出后，经过上面金属板中间的小孔，落到两板之间的匀强电场中，在强光照射下，观察者通过显微镜观察油滴的运动．大多数油滴在经过喷雾器喷嘴时因摩擦而带电，密立根通过实验测得数千个油滴所带电荷量，并分析得出这些电荷量都等于某个最小电荷量的整数倍，这个最小电荷量即电子所带电荷量．

从喷雾器喷出的小油滴可以视为球形，小油滴在空气中下落时受到的空气阻力大小跟它下落的速度v的大小成正比，即f=6πηr v，式中r为油滴的半径，η为粘度系数．

（1）实验中先将开关S断开，测出小油滴下落一段时间后达到匀速运动时的速度v₁，已知油的密度为ρ，粘度系数为η，空气的浮力远小于重力，可以忽略，试由以上数据计算小油滴的半径r．

（2）待小油滴向下运动的速度达到v₁后，将开关S闭合，小油滴受电场力作用，最终达到向上匀速运动，测得匀速运动时的速度v₁，已知两金属板间的距离为d，电压为U，试由以上数据计算小油滴所带的电荷量．

Board, But Not Boring

Roll the Dice and Take a Chance on Something New…

Are you vacationed-out, tired of video-gaming, waterlogged by too many trips to the pool and ready to scream if you see one more “SpongeBob” rerun?

In other words, are you bored with summer?

We’ve got a suggestion: Kill that boredom with some great board boredom games. We went to game expert Lizzy Palmer of Barston’s Child’s Play in the District and ask for suggestions. All the games you see on this page are a ton of fun, she said, and there are sure to be at least one or two that you don’t already have.

Maptangle

Borderline Games

Ages 7 and older, 4 to 6 players, $24.95

This clever take on the classic game of Twister challenges your gymnastic and geographic skills at the same time. A huge floor map of the world serves as the game board. There are lots of geographic elements: countries, oceans,  rivers, deserts, even man-made landmarks. A deck of cards tells you where to put one foot, then the other. The round is over when someone falls.

Jungle Speed

Ages 7 and older, 2 to 8

players, $25.99

This is a fast-paced shape-recognition game. A wooden totem (图腾柱) sits in the middle. Players flip (翻) over cards one at a time. When your card matches another, be the first to grab the totem so that you can give your card to the loser. But be careful: Some cards look the same but aren’t!

Enchanted Forest

Ravensburger Ages 6 and older, 2 to 6 players,

$24.99

A classic memory game. Take a winding path through the forest and check under the trees for

fairy-tale treasure. Remember what you saw so that when you need a particular treasure you can

go back to that tree to get it. Cool rule: You can split your dice (骰子) roll—for example, move five spaces in one direction and two in the other to land at the right tree.

Go fish for Wildlife Birdcage Press All ages, $9.95

Birdcage has several decks (副) of cards that are more like trading cards. You fish for sea creatures,  reptiles, wild animals. Each deck has instructions for several card games, and each card has great photos and fun facts. Great for a trip.

HedBanz Funrise Ages 6 and older, 2 to 6

players, $13.99

Put on a headband and slip in a card that shows an animal or thing. Everyone else can see it but you.Ask questions until you guess what it is—but do it before time runs out!

68. What’s the purpose of writing the article?  

A. To advertise several board games to attract potential consumers.

B. To introduce several board games for readers to pass the summer.

C. To try to persuade readers to give up video games and choose board games.

D. To make some suggestions on how to spend the long summer.

69. Suppose Doris, a mother with a six-year old boy, wants to buy some board games for her child. How many kinds of board games can she choose?

A. 2                     B. 3                              C. 4                              D. 5

70. Which of the following games will be the best choice for Mr Smith who wants to find an indoor game that can benefit both his daughter’s mind as well as her body?

A. Go Fish for Wildlife                                           B. Jungle Speed

C. Maptangle Borderline Games                       D. Hedbanz

71. Which of the following can match the games with their benefits to players?

(1) Enchanted Forest                                    a. to practice your quick response

(2) Maptangle Borderline Games    b. to practice your memory    

(3) Jungle Speed                                            c. to practice your geographic knowledge

(4) Go fish for Wildlife                         d. to increase the knowledge about animals

A. bacd                                 B. bcad                       C. cbad                       D. cdab

其他针叶木面多层板

易袭阴位的邪气是

A．风
B．寒
C．暑
D．湿
E．燥

阀控铅酸蓄电池一般采用（）设计，其电解液的密度为（）。