乳痈溃后乳汁自疮口流出，久不愈合，则形成( ) A．以上都不是 B．乳痨 C．乳

已知两圆半径分别为2和3，圆心距为d，若两圆没有公共点，则下列结论正确的是（　　）

A．0＜d＜1

B．d＞5

C．0＜d＜1或d＞5

D．0≤d＜1或d＞5

B

All of us eat every day, but most of us don’t understand nutrition. We often make mistakes in talking about good diet.

For example, many people think that foods such as rice, bread and potatoes will make one grow fat. In fact, these foods are very good to one’s health. They are good sources of many vitamins. And in comparison with steak and beef, they contain less amount of calories.

Some people don’t like canned(罐装的) or frozen vegetables, because they think fresh vegetables cooked at home are always better. This is again wrong. In fact, whether the vegetables are good or not depends more on how they are prepared. Overcooking, for example, destroys good qualities of vegetables. Vegetables cooked in too much water can use a large amount of vitamins.

It is widely believed extra vitamins provide more energy. But taking more than the body needs doesn’t make it function better.

It is also wrong to say that vegetables grown in poor, worn-out soil are lower in vitamins than vegetables grown in rich soil. The vitamins in our foods are in the plants themselves. They don’t come from the soil. However, the minerals(矿物质) in a plant depend on the minerals in the soil.

In short, there are many false ideas about nutrition. We need to correct them.

1. This passage is mainly about_______.

A. nutrition           B. vitamins            C. vegetables         D. health

2. Rice, bread and potatoes do good to people’s health mainly because_______.

A. they make people fat                      B. there are lot of vitamins in them

C. they contain less amount of calories compared with steak and beef.

D. both B and C.

3. Why don’t some people like canned or frozen vegetables? Because______.

A. they think fresh vegetables contain less vitamins

B. they think fresh vegetables contain more vitamins than the canned or frozen ones

C. they don’t think the canned or frozen vegetables are fresh

D. they don’t think the canned or frozen vegetables taste as good as the fresh ones

4. Which of the following is true according to the passage?

A. Many people know almost everything about nutrition.

B. Food such as rice, bread and potatoes make people fat.

C. vegetables grown in poor worn-out soil may have the same amount of vitamins as vegetables grown in rich soil.

D. extra vitamins provide less energy.

5. The point of the passage is that______.

A. the minerals in a plant depend on the minerals in the soil

B. people make mistakes when talking about good diet

C. taking more vitamins than the body needs doesn’t make it function better

D. vegetables cooked in too much water can lose a large amount of vitamins

（8分）用一定浓度的稀盐酸与稀NaOH溶液在左下图所示的装置中进行中和反应，通过测定反应过程中所放出的热量可计算中和热。已知强酸与强碱的中和热为57.3KJ/mol，水的比热容为4.2J/(g·℃)，有关热量与比热容的计算公式：Q=m×c×△t（Q为热量，m为物质的质量，c为比热容，△t物质温度的变化值）

回答下列问题：

（1）从实验装置上看，图中尚缺少的一种玻璃用品是：              

（2）将V₁ mL 1.0 mol/L HCl溶液和V₂ mL未知浓度的NaOH溶液混合均匀后测量并记录溶液温度，实验结果如图所示(实验中始终保持V₁＋V₂＝50 mL)。

下列叙述正确的是          

A．做该实验时环境温度为22 ℃

B．该实验表明化学能可以转化为热能

C．NaOH溶液的浓度约是1.00 mol/L

D．该实验表明有水生成的反应都是放热反应（3）V₁=30mL时HCl和NaOH恰好反应，根据题中所给数据算出的温度变化值约为

       （保留整数，计算时可将稀溶液的密度及比热容看成与水近似相同，且溶液混合时体积变化忽略不计）；而根据上图的温度变化可读出温度变化值约7 ℃；两者相比所测结果偏低，造成如此现象的原因有：

硬膜外穿刺针和导管误入血管的发生率约（）

A.0.01%～0.19%

B.0.2%～2.8%

C.3.0%～4.0%

D.4.1%～5.5%

E.5.6%～10%

怎样进行镜板的研磨（即抛光）工作？