试题与答案

某校学生高一年级有400人,高二年级300人,高三年级200人,现用分层抽样的方

题型:填空题

题目:

某校学生高一年级有400人,高二年级300人,高三年级200人,现用分层抽样的方法从所有学生中抽取一个容量为N样本,已知从高三学生中抽取的人数为10,那么N=______.

答案:

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Dear Editor,Last week,I made a survey among 30 boys and 30 girls in our school about their purpose of getting on the Internet.Both the boys and the girls like chatting...

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题型:选择题

读图,完成1—2题。

1、若图中甲、乙、丙分别代表大气污染、水污染和固体废弃物污染,则下列工厂及区位选择正确的是[ ]

A.①火电厂—布局在城市的河流下游

B.②水泥厂—布局在城市最小风频的下风地带

C.③钢铁厂—布局在市内交通便捷处

D.④化工厂—远离居民区和河流水源地

2、若图中甲、乙、丙分别代表动力、廉价劳动力和原料,则图中数码①-③依次代表的工业部门是[ ]

A.炼铝厂、纺织厂、集成电路厂

B.制鞋厂、炼铝厂、集成电路厂

C.电子装配厂、炼铝厂、钢铁厂

D.啤酒厂、炼铝厂、钢铁厂

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题型:阅读理解

Food sometimes gets poisoned with harmful things. A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious, but some types are deadly. The symptoms of food poisoning usually begin within hours of eating the poisoned food. Fever is one of the most common symptoms.

Certain microorganisms(微生物)cause most types of food poisoning. Bacteria and other microorganisms can poison eggs, meat, vegetables, and many other foods. After entering the body, these tiny living things release(释放)poisons that make people sick.

Some chemicals can also cause food poisoning. They are often added to food while it is being grown, processed, or prepared. For example, many farmers spray chemicals on crops to kill weeds and insects. Some people may have a bad reaction to those chemicals when they eat the crops.

Some plants and animals contain natural poisons that are harmful to people. These include certain kinds of seafood, grains, nuts, seeds, beans, and mushrooms.

When people handle food properly, the risk of food poisoning is very small. Microorganisms multiply rapidly in dirty places and in warm temperatures. This means that people should never touch food with dirty hands or put food on unwashed surfaces. Food should be kept in a refrigerator to stop microorganisms from growing. Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it. Finally, people should not eat wild mushrooms or other foods that grow in the wild. Some of these foods may contain natural materials that are poisonous to humans. In addition, some types of fish can be poisonous.

Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons, they must go to the hospital right away to have their stomachs emptied.

1. Which of the following statements is NOT true?

A. Food when poisoned can make people sick.

B. Food poisoning means death.

C. Food poisoning comes in varieties.

D. Food poisoning can be serious.

2.We know from the passage that the symptoms of food poisoning__________.

A.are always accompanied by a fever

B.are too common to be noted

C.can be noticed within hours

D.can he ignored

3.Food poisoning can be caused by all the following EXCEPT__________

A.some chemicals

B.low temperatures

C.some tiny living things

D.certain natural materials

4.From Paragraph 5,we can learn that__________

A.mushrooms should not be eaten

B.vegetables are safer than meat and seafood

C.natural poisons are more dangerous than chemicals

D.different types of food should be handled differently

5.It can be inferred from the passage that__________

A.natural materials are safe in food processing

B.chemicals are needed in food processing

C.food poisoning can be kept under control

D.food poisoning is out of control

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