极点

阅读下面的材料，根据要求作文。

讲评课上，老师读了几位同学的作文后疑惑不解地问大家：你们为什么都喜欢说自己是“十六岁的花季”？同学们回答说，因为有同名电视剧，而且现在已经约定俗成了。老师听了这个回答，若有所思地说：“你们为什么没想到自己是一棵树呢？一棵有十六道年轮的树已经很壮实了。”同学们默默不语。

你觉得你们是花还是树呢？请以此为话题写一篇文章。立意自定，除诗歌外文体不限，不少于800字。

(16分)如图所示，直角坐标系xoy的第一象限内有场强为E方向沿x轴负向的匀强电场，第二象限内有方向沿y轴负向的匀强电场，在的区域内有方向垂直坐标平面的匀强磁场．一质量为m、电荷量为q的正粒子(不计重力)，从P()点由静止开始运动， 通过第二象限后经点再进入y≤0区域，并恰好经过坐标原点O.求

(1)第二象限内匀强电场的场强．

(2)y≤0区域内匀强磁场的磁感应强度B．

(3)粒子从P到0经历的时间．

霍乱的首选是：

A．氯霉素

B．头孢曲松

C．阿莫西林

D．多西环素

E．阿米卡星

Vincent Van Gogh was not always an artist. In fact, he wanted to be a church minister and was even sent to the Belgian mining community of Borinage in 1879. He discovered that the miners there endured terrible working conditions and poverty-level wages. Their families were skin-and-bone and struggled simply to survive. He felt concerned that the small pay he received from the church allowed him a reasonable lifestyle, which, in contrast, seemed to him unfair.

One cold February evening, while he watched the miners trudging home, he spotted an old man staggering toward him across the fields, wrapped in a burlap(粗麻布) bag for warmth. Van Gogh laid his own clothing out on the bed, set aside enough for one change, and decided to give the rest away. He gave the old man a suit of clothes and he gave his overcoat to a pregnant woman whose husband had been killed in a cave-in.

He lived on starvation food and spent his salary on food for the miners. When children in one family caught typhoid fever, though feverish himself, he packed up his bed and took it to them.

A wealthy family in the community offered him free room and board, Van Gogh declined the offer, stating that it was the final temptation (诱惑) he must reject if he was to faithfully serve his community of poor miners. He believed that if he wanted them to trust him, he must become one of them. And if they were to learn of the love of God through him, he must love them enough to share with them.

He was acutely aware of the big difference between words and actions. He knew that our lives always speak louder and clearer than our words. Maybe that is why Francis of Assisi often said to his monks, “Wherever you go, preach(讲道). Use words if necessary.”

Others are “listening” carefully to your actions. What are you saying to them?

1. We can infer form the passage ____________.

A. our lives always speak louder and clearer than our words

B. the miners there worked under excellent working conditions

C. the ministers lived a much better and easier life than the miners at the time

D. Van Gogh himself offered to work in the Belgian mining community of Borinage in 1879.

2. What does the underlined word “trudging” in the second paragraph mean?

A. Moving very quickly              B. Moving with quick light steps

C. Walking slowly for pleasure.         D. Walking with slow heavy steps.

3. According to the passage, which of the following words can best describe Van Gogh?

A. Ambitious and aggressive.          B. Considerate and sympathetic

C. Greedy and selfish.                D. Determined and grateful

4. What does the last paragraph want to tell us?

A. Use words if necessary             B. Actions speak louder than words

C. Rome was not built in a day.         D. Where there is a will there is a way.

硫是钢中的有害元素，它最大的危害是使钢产生（）。