烟雾为几级致癌物（）A.级 B.B1级 C.B2级

阅读理解。

     I was very disappointed not to be able to go to the jazz concert last Friday. The advertisement in the

paper said that you could buy tickets at the theatre box in Richland Hills any day between 10:00 and

4:00.Since I work from 9:00 to 5:30, the only time I could go to the theatre was during my 45-minute

lunch break. Unfortunately, the theatre is on the other side of the town, and the bus service between my

office and Richland Hills is not very good. But if you are lucky, you can make the round trip in 45 minutes. Last Monday. I stood at the bus stop for 15 minutes waiting for the bus. By the time I saw one come

around the corner, there was not enough time left to make the trip.So I gave up and went back to the

office. The same thing happened on Tuesday, and again next day. On Thursday, my luck changed. I got

on a bus right away and arrived at the theatre in exactly 20 minutes. When I got there, however, I found

a long line of people at the box office. I heard one man say he had been waiting in line for over an hour.

Realizing I would not have enough time to wait in line, I caught the next bus and headed back across the

town. By Friday I realized my only hope was to make the trip by taxi, it was expensive, but I felt it would

be worth it to hear the concert. The trip by taxi only took 10 minutes, but felt like an hour to me. When I

got to the theatre, I was relieved to see that nobody was waiting in line. The reason, however, I quickly

discovered, was that they had already sold all the tickets.

1.The man learned          that there would be a concert last Friday.

A. from his friends

B. from one of his work-mates

C. over the radio

D. from the newspaper

2. He tried to go to the theatre every day but managed to get there only _______.

A. once

B. twice

C. three times

D. four times

3.The underlined word "relieved" may best be replaced by ___________.

A. surprise

B. pleased

C. puzzled

D. sorry

书写下列化学反应的文字表达式并注明反应类型

（1）氢气燃烧_________________（　 ）

（2）硫燃烧___________________（ 　）

（3）铁在氧气中燃烧__________________（ 　）

（4）加热氯酸钾与二氧化锰混合物__________________（ 　）

位于CPU和主存DRAM之间、容量较小但速度很快的存储器称为　【 】　。

因不可抗力导致个体工商户无法经营的，登记机关应当依法办理个体工商户注销登记手续。

天线一般要在避雷针（）度保护区域内，山区及多雷区则要求天线在避雷针（）度保护区域内。