23. I can't say which wine is stronger-it's a (n)_____ of personal taste.

A．affair　　 B．event　　 C．matter　　 　D．variety

22. Our public transportation system is not ________ for the needs of people.

A. complete　　　 B. adequate　　 C. good　　　　 D. normal

第一节：单项选择 (共20小题；每小题1分，满分20分)

21. One day I _______ a newspaper article about the retirement of an English professor at a nearby state college.

A. came across　　 B. came about　 C. came over　　 D. came out

第二节: 听取信息(共5小题，每小题1分，满分5 分)

听下面一段对话。请根据题目要求，从所听的内容中获取必要的信息，

填入标号为16-20的空格中。录音读两遍。你有60秒钟的作答时间。

Service Information at North London Arts Cinema

第一节: 听力理解(共15小题；每小题1分，满分15分)

每段播放两遍。各段后有几个小题，各段播放前每小题有5秒钟的阅题时间。请根据各段播放内容及其相关小题，在5秒钟内从题中所给的A、B、C 项中，选出最佳选项，并在答题卡上将该项涂黑。

听第1段对话，回答第1-3题。

1．Why was the man late for class?

A．He got up late.　　　　　　　　　　　 　

B．Due to the heavy traffic.　　

C．He didn’t catch the bus.

2．What can we know from the dialogue?

A．A car pool is a kind of organization that owns cars and sends people to work.

B．Car pool is the name of a company that helps people hire cars .

C．People who join a car pool live nearby and ride in one car.

3．How does the woman know so much about the car pool?

A．She has joined a car pool.

B．She has read about it in the paper.

C．She works in it.

听第2段对话，回答第4---6题。

4．Which of the following is TRUE about the car?

A. It’s new and small .　　　 　　

B. It’s old and bought in America.　　　　　

C. It’s second-hand and from another country.

5．Why does Mike’s friend want to sell the car?

A. She needs money to buy a new house.　

B. She can’t afford to keep it in the city.

C. She lives near her workplace.

6．How much does the man agree to pay for the car?

A. More than 5,000 dollars.　　

B. Less than 5,000 dollars.　

C. Not mentioned.

听第3段对话，回答第7---9题。

7．Where does the conversation most probably take place?

A. In the post office.　

B. In a shopping center.　

C. At the railway station.

8．What can we learn from the dialogue?

A. The man has to write down the return address as required.　　

B. The man bought two sets of glasses.　　　

C. The man has to pay more than $8.20.

9．Which statement of the following is TRUE according to the dialogue?

A. The man has to fill in a form　　　

B. If the man chooses the second class, it will take ten days to arrive.

C. It is a rule to write down the return address.

听第4段对话，回答第10---12题。

10．What is the telephone number of Blue Travel Agency?

A. 7489932.　　 B. 7389932.　　　　 C. 7489942.

11 When does Jill want to go to New York?

A. In May.　　　 B. In April.　　　　 C. In March.

12．In what way will Jill return?

A. By plane.　　　 B. By train.　　　　 C. By car.

听第5段独白，回答第13---15题。

13．Why did the man lose his temper?

A. Because the bird couldn’t repeat his master’s name.　　

B. Because the bird screamed all day long.　　　

C. Because the bird failed to say the name of the town.

14．Who killed the three chickens?

A. The man in the kitchen.

B. The pet bird.

C. The fourth chicken.

15．Why was the man shocked at the scene the next morning?

A. The bird had finally understood his threat to kill it.

B. The bird managed to escape from the chicken house.

C. The bird had learned to scream back at him.

9.某钢材厂要将两种大小不同的钢板截成A、B、C三种规格，每张钢板可同时截得三种规格小钢板的块数如下表：

每张钢板的面积，第一种为1m²，第二种为2 m²，今需要A、B、C三种规格的成品各12、15、27块，请你们为该厂计划一下，应该分别截这两种钢板多少张，可以得到所需的三种规格成品，而且使所用钢板的面积最小？只用第一种钢板行吗？

　 解：设需要截第一种钢板x张，第二种钢板y张，所用钢板面积为z m²，则

　　 目标函数z=x+2y

作出可行域如图

作一组平行直线x+2y=t，

2x+y=15 　 　 　 　 　 　 x+y=12　　　 x+3y=27 　 x+2y=0

由

可得交点，

但点不是可行域内的整点，其附近的整点(4，8)或(6，7)可都使z有最小值，

且z_min=4+2×8=20 或z_min=6+2×7=20

若只截第一种钢板，由上可知x≥27，所用钢板面积最少为z=27(m²);

若只截第二种钢板，则y≥15，最少需要钢板面积z=2×15=30(m²).它们都比z_min大，因此都不行.

8. 已知1x－y2,且2x+y4,求4x－2y的范围.

错解：由于　1x－y2　①,

2x+y4　　②,

①+② 得32x6　　 ③

①×(－1)+② 得：02y3　 ④.

③×2+④×(－1)得. 34x－2y12

错因：可行域范围扩大了.

正解：线性约束条件是：

令z＝4x－2y，

画出可行域如右图所示，

由得A点坐标(1.5，0.5)此时z＝4×1.5－2×0.5＝5.

由得B点坐标(3，1)此时z＝4×3－2×1＝10.

　 54x－2y10

7. 由围成的几何图形的面积是多少?

解析：如下图由围成的几何图形就是其阴影部分，

且.　　　

5.不等式组表示的平面区域内的整点(横坐标和纵坐标都是整数的点)共有_____个.

解析:(1，1)，(1，2)，(2，1)，共3个.

6(汕头市金山中学2009届高三上学期11月月考)

某工厂生产甲、乙两种产品，已知生产每吨甲、乙两种产品所需煤、电力、劳动力、获得利润及每天资源限额(最大供应量)如下表所示：

产品 　　　 消耗量 资源	甲产品 (每吨)	乙产品 (每吨)	资源限额 (每天)
煤(t)	9	4	360
电力(kw·h)	4	5	200
劳力(个)	3	10	300
利润(万元)	6	12

　问：每天生产甲、乙两种产品各多少吨，获得利润总额最大？

解：设此工厂应分别生产甲、乙两种产品x吨y吨，获得利润z万元…………1分

　 依题意可得约束条件：…………………………5分

　 　　　　　　　　　　　　　　　　　　　　　　　　　　(图2分)

　　 利润目标函数………………………………8分

如图，作出可行域，作直线向右上方平移至l₁位置，直线经过可行域上的点M，且与原点距离最大，此时取最大值。……10分

解方程组………………………………12分

所以生产甲种产品20t，乙种产品24t，才能使此工厂获得最大利润。……14分

综合拔高训练

3.(广东省梅州、揭阳两市四校2008届高三第三次联考)已知点的坐标满足条件，点为坐标原点，那么的最大值等于_______,最小值等于____________.　　　

解析:　 从图中看出 　,

，

4(惠州市2008届高三第三次调研考试)

已知点P(x,y)满足条件y的最大值为8，则　　　 .

解析：画图，联立方程得，代入