某公司以单价10元每年购买某种产品8000件。每次订货费用为30元，单位库存维护费按

美国联邦负责食品安全的部门主要有农业部、卫生部和环境保护署，这些部门按照食品的()分工负责食品安全的监管。

A.环节

B.种类

C.流程

D.形态

阅读理解。

     I had a dream - a strange dream that has helped me to understand Eric much better. 　　

     In the dream, Eric looked angry and said,"Melissa, I have something to tell you." 　　

     I've lived with Eric for more than five years. He is the cutest thing I've ever seen. I buy him fish and

milk and lots of toy mice once a week. I even bought a small house for him, because he sometimes likes

to be left only by himself. I love him with all my heart, and give him all I love. 　　

     But what has gone wrong? In the dream Eric said angrily,"I don't like fish. I don't like milk. And toy mice?

Are you crazy? I'm not a cat. And I don't want to be a cat, either!" Then he ran back to his small house. 　　

      After the dream, I know better: dogs don't like fish or milk. And surely they do not like toy mice. Most

important of all, they will let you know when they are really angry!

1. What can we learn about Eric in the reading?

A. He likes cats.

B. He is Melissa's pet.

C. He is four years old.

D. He enjoys talking with Melissa.

2. Why was Eric angry in the dream?

A. He did not have many friends.

B. Melissa loved him the wrong way.

C. Melissa did not take him out for a long time.

D. There were too many mice in Melissa's house.

3. Why did Melissa buy a house for Eric?

A. Eric did not sleep well in her room.

B. Eric needed more space for his toys.

C. Eric was too big to share a bed with her.

D. Eric did not always like to be with others.

—Hi, Mary. It never entered my head that you’d come. What a surprise!

—I’m on a business trip in the city and I ______ in on you.

A．dropped

B．drop

C．had dropped

D．have dropped

直流电动机的机械制动包括液压制动和机械闸制动。

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