如图所示，一个质子（11H）和一个α粒子（42He）先后垂直于磁场方向进入同一匀

硝酸酯类治疗心绞痛主要机理是可使静脉张力_____引起外周静脉回心血量_____，从而减轻心脏_____负荷。

阅读下列反映国际格局演变的相关材料，然后回答问题

材料一：

巴黎和会“三巨头”
华盛顿会议

材料二：“美国在世界上处于领导地位。……凯撒、成吉思汗、路易十四、拿破仑或其他任何一个伟大的领袖所担负的责任，都不能同美国总统今天所担负的责任相比拟。”――1945年4月16日杜鲁门总统的谈话材料三：“世界新秩序……有很多权力中心，每一个都独立活动。……美国仅仅是一个大国，还有可与美国匹敌的其他国家，如日本、欧洲在一定程度上也是这样，再过几年还有中国，以及前苏联中的某些国家。”――1993年亨利·基辛格的谈话请回答：（1）通过材料一中两次会议的召开，形成了怎样的国际关系格局？____________________________________________________________________________________________（2）材料二中拿破仑被称为“伟大的领袖”，请结合所学知识举一例说明。杜鲁门的这段谈话表明了美国有何企图？____________________________________________________________________________________________（3）根据材料三说明当今世界格局呈现出怎样的发展趋势？请简述中国在当前世界格局中所处的地位。____________________________________________________________________________________________

下列各句中冒号使用正确的一项是

A．省教育厅在给红旗村建的纪念碑上刻着：“办学功绩，永垂青史”八个大字。

B．我们赞成：既要关心自己的兄弟姐妹，又要关心别人的兄弟姐妹。

C．“纪律要严明，”陈厂长说：“纪律不严明，不能打胜仗。”

D．比赛开始了，同学们高喊着：“加油!加油!”的口号为运动员加油。

That cold January night, I was growing sick of my life in San Francisco. There I was, walking home at one in the morning after a tiring practice at the theatre. With opening night only a week away, I was still learning my lines. I was having trouble dealing with my part-time job at the bank and my acting at night at the same time. As I walked, I thought seriously about giving up both acting and San Francisco. City life had become too much for me.

As I walked down empty streets under tall buildings, I felt very small and cold. I began running, both to keep warm and to keep away from any possible robbers (抢劫犯). Very few people were still out except a few sad-looking homeless people under blankets.

About a block from my apartment (公寓房间), I heard a sound behind me. I turned quickly, half expecting to see someone with a knife or a gun. The street was empty. All I saw was a shining streetlight. Still, the noise had made me nervous, so I started to run faster. Not until I reached my apartment building and unlocked the door did I realize what the noise had been. It had been my wallet falling to the sidewalk.

Suddenly I wasn’t cold or tired anymore. I ran out of the door and back to where I’d heard the noise. Although I searched the sidewalk anxiously for fifteen minutes, my wallet was nowhere to be found.

Just as I was about to give up the search, I heard the garbage truck (垃圾车) pull up to the sidewalk next to me. When a voice called from the inside, “ Alisa Camacho?” I thought I was dreaming. How could this man know my name? the door opened, and out jumped a small red-haired man with an amused look in his eyes. “Is this what you’re looking for?” he asked, holding up a small square shape.

It was nearly 3 A.M. by the time I got into bed. I wouldn’t get much sleep that night, but I had gotten my wallet back. I also had gotten back some enjoyment of city life. I realized that the city couldn’t be a bad place as long as people were willing to help each other.

1. How did the writer feel when she was walking home after work?

A. Cold and sick           B. Fortunate and helpful

C. Satisfied and cheerful      D. Disappointed and helpless

2. From the first paragraph, we learn that the writer was busy ______.

A. solving her problem at the bank         B. taking part in various city activities

C. learning acting in a n evening school      D. preparing for the first night show

3. On her way home the writer _______.

A. lost her wallet unknowingly               B. was stopped by a garbage truck driver

C. was robbed of her wallet by an armed man   D. found some homeless people following her

4. In the fifth paragraph, why did the writer say she was dreaming?

A. Someone offered to take her back home. B. A red-haired man came to see her.

C. She heard someone call her name D. Her wallet was found in a garbage truck.

5. From the text, we can infer that the writer _________.

A. would stop working at night       B. would stay on in San Francisco

C. would make friends with cleaners    D. would give up her job at the bank

电报的发明者是：（）

A、贝尔

B、香农

C、莫尔斯

D、霍克哈姆