第二次流通现代化的时间是指（）。 A.公元1500年以来 B.伴随着农业社会向工业社

阅读理解。

　　I am an English teacher in an international school. I have students from all

over the world. Let me tell you about my favorite students.

　　Matt comes from New York. He loves rap music. When he walks between 

classmates, they respect (尊敬) him because he's big for his age. In his free time

he often watches action movies and practices kung fu. Today he takes part in a

kung competition.

　　Kate is another one of my favorite students. She is a tall, beautiful girl from

London. She is a good student and she's always studying. Sometimes she can't

sleep because she thinks too much about her lessons. Her favorite sport is

swimming. She says she wants to be a doctor when she leaves school. I hope

she will succeed!

1. Where' are the students in the international school from?

A. New York.              

B. London.

C. All over the world.      

D. America.

2. What does Matt do today?

A. He practices kungfu.

B. He joins in a kung competition today.

C. He takes an exam.

D. He watches an action movie.

3. Why do Matt's classmates respect him?

A. Because he is old.

B. Because he is thin for his age.

C. Because he is tall and strong for his age.

D. Because he is a dangerous boy.

4. What country does Matt come from?

A. England.                  

B. France.

C. The USA.                  

D. China.

5. What problem does Kate have?

A. Sometimes she can't go to bed.

B. Sometimes she can't fall asleep.

C. She is a good girl.

D. She is always studying.

计算题：

取某水样20.00ml，加入0.025 0mol／L重铬酸钾溶液10.00m1，回流2h后，用水稀释至140ml，用0.1025mol／L硫酸亚铁铵标准溶液滴定，消耗22.80ml，同时做全程序空白，消耗硫酸亚铁铵标准溶液24.35ml，试计算水样中COD的含量。

请阐述食品安全管理体系第一阶段与第二阶段审核目的的不同。

简述儿童溺水的预防及干预措施。