洋葱是生物学实验中常用的实验材料。利用紫色洋葱鳞片叶的外表皮细胞在光照下进行质壁分离

《送董邵南序》作者写此序的意图是什么？（用原文回答。）

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We’re surrounded by chemistry in everyday life. Sometimes it is easy to see, like when your science teacher does a big experiment in class. At other times, it can be pretty hard to see everyday chemistry at work, but nearly everything you touch or use has some element of chemistry in it.

Something as simple as toothpaste contains at least three chemicals, if not more. It is the mixture of them and its chemical reaction that keeps your teeth clean. Other things you use every day are created by chemistry, such as hair products, shampoo and soap. Adding detergent (洗涤剂) to water involves chemistry. Without chemistry, we would never have known that we need soap to get the oil out of clothes or skin. Chemistry not only helps us make products for use, but it also helps us understand the world around us. Chemistry helps us understand what the ozone layer (臭氧层) is and how it protects us. Chemistry also gives us sunscreen to protect us from the sun. Thanks to chemistry, we know bleach (漂白剂) can’t be mixed with vinegar(醋), because it can produce poisonous gas.Without chemistry, we wouldn’t have fireworks displays on important days.

Chemistry plays a big role in food preparation. Cooking food causes it to go through a chemical change. That is why cooked food often tastes different from raw food. Baking is a great example of chemistry. Too much or too little of any ingredient（成分，尤指烹饪） makes a difference to the result of baking, for example, the dough (面团) won’t rise or the cake will be flat.

Chemistry isn’t something that just lives in a lab; it’s something that you meet hundreds of times every day. Knowing how chemistry works will give you a greater understanding of the science behind some of the simplest-looking things.

小题1:What’s the main idea of Paragraph 1?

A．Chemistry is easy to see around us.

B．Sometimes chemistry is hard to see around us.

C．How a science teacher does a big experiment.

D．Few things in everyday life contain chemistry.小题2:The following actions are about chemistry EXCEPT _____.

A．cleaning teeth with toothpaste

B．washing hair with hair products

C．using soap to get the oil out of clothes

D．washing your face with water小题3:The underlined word “poisonous” in Paragraph 3 means _____.

A．harmful

B．healthy

C．fresh

D．pleasant小题4:Which one is TRUE according to Paragraph 4?

A．One can’t find chemistry when cooking food.

B．Chemistry plays an important part in food mak-ing.

C．That dough rises is nothing to do with chemistry.

D．A flat cake is the result of too many ingredients.小题5:Which of the following would be the best title for the text?

A．Chemistry Around the House

B．Chemistry in Science

C．Chemistry for Dinner

D．Chemistry in everyday life

以“三王文章”著称的是以下哪座名楼( )

A．黄鹤楼
D．岳阳楼
C．滕王阁
D．鹳雀楼

轻度哮喘首选的支气管解痉剂为

A．舒喘灵

B．氨茶碱

C．异丙基阿托品

D．色甘酸二钠

E．青霉素

建设工程招投标中，投标人的投标应能够满足招标文件的实质性要求，并且投标价格最低。