甲烟草公司提供烟叶委托乙公司加工一批烟丝。甲公司将已收回烟丝中的一部分用于生产卷烟，

如图是测量带电粒子质量的仪器工作原理示意图．设法使某有机化合物的气态分子导入图中所示的容器A中，使它受到电子束轰击，失去一个电子变成为正一价的分子离子．分子离子从狭缝s₁以很小的速度进入电压为 U的加速电场区（初速不计），加速后，再通过狭缝s₂、s₃射入磁感强度为 B的匀强磁场，方向垂直于磁场区的界面 PQ．最后，分子离子打到感光片上，形成垂直于纸面且平行于狭缝s₃的细线．若测得细线到狭缝s₃的距离为d，

（1）导出分子离子的质量m的表达式．

加强党的执政能力建设，必须坚持的核心是

A．保持党同人民群众的血肉联系

B．建设高素质的干部队伍

C．改革和完善党的领导体制和工作机制

D．加强党的基层组织和党员队伍建设

阅读理解。

         Childhood was an illusion(错觉)  and the illusion was this:everything was bigger. No, I

ruean everything, not just houses and shops and grown-ups, but colors and flowers and joumeys,

especially journeys which  seemed endless. "Are we there yet, Daddy?"

        Funfairs(游乐场)  were huge things that spread for miles around you with noise and lights

and exciting  danger. Rainy days at home when you were ill seemed  to last for ever. Being a

grown-up yourself was an un- thinkable distant possibility. Every sound was louder, every

game was grander, every pain was unbearable.

        As I've grown old, life has become smaller. Tastes  have dulled. Surprises have turned into

shocks. Days go  by unnoticed. How can I regain childhood when it was  an illusion?

        I have only one repeatable and wonderful way and even in this way I can regain only part

of that larger  world.l can play upon the stage like a child and make  the crowd laugh with them,

sonletimes helplessly like a child, and then, even though I'm a sixty-one-year-old man, I can almost

catch the colors and sounds and  stillness of those bigger years when I was little.

1. How does the author feel about his childhood?      

A. It was endless.

B. It was unpleasant.

C. He is glad that it is over.

D. He misses it as a grown-up.

2. The author thinks that everything was bigger in childhood because     ___  

A. children could not make proper judgments

B. children were cunous and eager about life

C. things appeared really big in children's eyes

D. to grow up seemed so long for children

3.The world seems to have become smaller to the author because _______.    

A. life is disappointing

B. time goes by too fast

C. he has had too many surprises

D. foods no longer taste delicious

4. The author enjoys playing on the stage so as to                 

A. act like a child

B. live an unusual life

C. make the crowd laugh

D. regain his childhood

( )是指物业管理区域内用于治安、消防、车辆管理及紧急呼叫等安全防范的技术设备系统。

A．公共管理安防系统

B．物业管理安防系统

C．安防系统

D．防范系统

在变电站内使用起重机械时，应安装接地装置，接地线应用多股软铜线，其截面应满足接地短路容量的要求，但不得小于（ ）mm2 。

A． 25.0

B．16.0

C．10.0

D．35.0