锡膏按（）原则管理使用。

阅读短文，选择正确选项。

       Do you need useful and interesting books? Here we've got plenty for you.

       Successful Fishermen

       Fishing is a healthy hobby. You can enjoy fresh air when you go fishing in the countryside. This book will

teach you how to choose fishing places and how to make good fishing rods (竿) easily. Many kinds of fishing

skills are shown in the book. Read it and you will become a more successful fisherman.

       Best Learners 

       This book can give you the answers to the questions most often asked by parents, teachers and students

themselves. Read this book and learn:

       ● What the three difficulties in study are and what to do with them.

       ● What to do if you are not interested in a subject you are studying.

       ● Twenty-six simple exercises to help you study easily and fast. You will get more from this book. For

younger students, you can buy Learn to Study for Beginners. It is easier to understand.

       How to Keep Pets

       A pet can be our best friend. Do you have pets in your house? Are they in good shape? This book not only

offers you many colorful pictures of lovely pets, but also provides you with the knowledge about:

      ●How to choose right pets for yourself.

      ●How to build houses or nests (窝) for your pets.

      ●How to feed the pets and how to keep them clean. 

       Buy this book and you will learn more.

       We have many other books on sale. For more information enter www. knowbetter. com. If you buy two

or more books at a time, you'll get 10% off.

1. If you buy and read Successful Fishermen, you will ______. [ ]

A. go to the countryside

B. know where to buy fishing rods

C. know how to cook fish

D. learn how to choose fishing places

2. You can              for more information about other books according to the passage. [ ]

A. call the writer

B. go to the shop

C. search the Internet

D. ask the clerk

3. You can most probably (可能) find this passage in a             . [ ]

A. story

B. report

C. dictionary

D. newspaper

（），是我国创造教育的首创者。

论述食品中水分与溶质间的相互作用。

在金刚石的网状结构中，含有由共价键形成的碳原子环，其中最小的环上有______（填数字）个碳原子，每个碳原子上的任意两个C-C键的夹角都是______（填角度）．

重金属中毒时用下列哪一种解毒药效果最好（）

A.依地酸钙钠（EDTACa-NA.

B.二乙烯三胺五乙酸三钠钙（DTPA.

C.二巯丙醇（BAL）

D.二巯丙磺钠（Na-DMPS）

E.二巯丁二钠（DMS）