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a) \(\sqrt[3]{27}-\sqrt[3]{-8}-\sqrt[3]{125}=\sqrt[3]{3^3}+\sqrt[3]{2^3}-\sqrt[3]{5^3}=3+2-5=0\)
b) \(\frac{\sqrt[3]{135}}{\sqrt[3]{5}}-\sqrt[3]{54}.\sqrt[3]{4}=\sqrt[3]{\frac{135}{5}}-\sqrt[3]{54.4}=\sqrt[3]{27}-\sqrt[3]{216}=3-6=-3\)
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 55 to 64.
Overpopulation, the situation of having large numbers of people with too few resources and too little space, is closely associated with poverty. It can result from high population density, or from low amounts of resources, or from both. Excessively high population densities put stress on available resources. Only a certainnumber of people can be supported on a given area of land, and that number depends on how much food and other resources the land can provide. In countries where people live primarily by means of simple farming, gardening, herding, hunting, and gathering, even large areas of land can support only small numbers of people because these labor-intensive subsistence activities produce only small amounts of food.
In developed countries such as the United States, Japan, and the countries of Western Europe, overpopulation generally is not considered a major cause of poverty. These countries produce large quantities of food through mechanized farming, which depends on commercial fertilizers, large-scale irrigation, and agricultural machinery. This form of production provides enough food to support the high densities of people in metropolitan areas.
A country’s level of poverty can depend greatly on its mix of population density and agricultural productivity. Bangladesh, for example, has one of the world’s highest population densities, with 1,147 persons per sq km. A large majority of the people of Bangladesh engage in low-productivity manual farming, which contributes to the country’s extremely high level of poverty. Some of the smaller countries in Western Europe, such as the Netherlands and Belgium, have high population densities as well. These countries practice mechanized farming and are involved in high-tech industries, however, and therefore have high standards of living.
At the other end of the spectrum, many countries in sub-Saharan Africa have population densities of less than 30 persons per sq km. Many people in these countries practice manual subsistence farming; these countries also have infertileland, and lack the economic resources and technology to boost productivity. As a consequence, these nations are very poor. The United States has both relatively low population density and high agricultural productivity; it is one of the world’s wealthiest nations.
High birth rates contribute to overpopulation in many developing countries. Children are assets to many poor families because they provide labor, usually for farming. Cultural norms in traditionally rural societies commonly sanction the value of large families. Also, the governments of developing countries often provide
little or no support, financial or political, for family planning; even people who wish to keep their families small have difficulty doing so. For all these reasons, developing countries tend to have high rates of population growth.
From "Poverty" by Thomas J. Corbett
Which of the following is given a definition in paragraph 1?
- A. Poverty
- B. Population density
- C. Overpopulation
- D. Simple farming
-
Câu 2:
What will suffer when there are excessively high population densities?
- A. Available resources
- B. Farming methods
- C. Land area
- D. Skilled labor
-
Câu 3:
The phrase “that number” in paragraph 1 refers to the number of ______.
- A. resources
- B. countries
- C. people
- D. densities
-
Câu 4:
In certain countries, large areas of land can only yield small amounts of food because ______.
- A. there is an abundance of resources
- B. there is no shortage of skilled labor
- C. there are small numbers of laborers
- D. there is lack of mechanization
-
Câu 5:
Bangladesh is a country where the level of poverty depends greatly on ______.
- A. population density in metropolitan areas
- B. both population density and agricultural productivity
- C. its population density only
- D. its high agricultural productivity
-
Câu 6:
The phrase “engage in” in paragraph 3 is closest in meaning to ______.
- A. escape from
- B. look into
- C. give up
- D. participate in
-
Câu 7:
The word “ infertile ” in paragraph 4 probably means ______.
- A. impossible
- B. unproductive
- C. disused
- D. inaccessible
-
Câu 8:
Which of the following is TRUE, according to the passage?
- A. In sub-Saharan African countries, productivity is boosted by technology.
- B. There is no connection between a country’s culture and overpopulation.
- C. All small countries in Western Europe have high population densities.
- D. In certain developed countries, mechanized farming is applied.
-
Câu 9:
Which of the following is a contributor to overpopulation in many developing countries?
- A. High-tech facilities
- B. High birth rates
- C. Economic resources
- D. Sufficient financial support
-
Câu 10:
Which of the following could be the best title for the passage?
- A. High Birth Rate and its Consequences
- B. Poverty in Developing Countries
- C. Overpopulation: A Worldwide Problem
- D. Overpopulation: A Cause of Poverty
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Giải:
a) \(\sqrt[3]{27}-\sqrt[3]{-8}-\sqrt[3]{125}=3-\left(-2\right)-5=3+2-5=0\)
b)\(\frac{\sqrt[3]{135}}{\sqrt[3]{5}}-\sqrt[3]{54}\cdot\sqrt[3]{4}=\frac{\sqrt[3]{27\cdot5}}{\sqrt[3]{5}}-\sqrt[3]{54\cdot4}=\frac{\sqrt[3]{27}\cdot\sqrt[3]{5}}{\sqrt[3]{5}}-\sqrt[3]{216}=3-6=-3\)
11. The teenagers aren’t buying that model these days.
A. That model isn’t being bought by the teenagers these days.
B. That model isn’t bought these days by the teenagers.
C. On these days that model isn’t being bought due to the teenagers.
D. Because of that model isn’t being bought these days by the teenagers
12. People say that he is the most experienced teacher of English.
A. He is said to be the most experienced teacher of English.
B. He is said the most experienced teacher of English.
C. He said the teacher of English is most experienced.
D. That he is the most experienced teacher of English is said by people.
13. People believe that he is a good teacher.
A. It is believed that he was a good teacher. B. He is believed to be a good teacher.
C. They were really believed he is a good teacher. D. He is believed to have been a good teacher.
14. It is thought that he has died a natural death.
A. He is thought to have died a natural death. B. He is thought to be dying a natural death.
C. He is thought to have been dying a natural death. D. He is thought to die a natural death.
15. The coach said, “It’s time for you to go home, boys!”
A. The coach told the boys that it was time for you to go home.
B. The coach tells the boys that it was time for them to go home.
C. The coach told the boys that it is time for them to go home.
D. The coach told the boys that it was time for them to go home.
16.“Why don’t you go with me?” she asked me.
A. He asked me why I don’t go with him. B. He asked me why didn’t I go with him.
C. He asked me why I didn’t go with him. D. He asked me why he didn’t go with me.
17. Why don’t we recycle bottles and cans?
A. We must recycle bottles and cans, mustn’t we? B. What do we recycle bottles and cans for?
C. Shall we recycle bottles and cans? D. How can we recycle bottles and cans?
18. “Why don’t you use the new car, Mr Son?” said Nam.
A. Nam made Mr Son to use the new car. B. Nam asked Mr Son not to use the new car.
C. Nam suggested that Mr Son use the new car. D. Nam suggested that Mr Son uses the new car.
19“Why don’t you use the new car, Mr. Son?” said Nam
A. Nam made Mr. Son to use the new car. B. Nam asked Mr. Son not to use the new car.
C. Nam suggested that Mr. Son use the new car. D. Nam suggested that Mr. Son uses the new car.
20.“You should not lend Susan any more money, Linda” said Nancy.
A. Nancy advised Susan not to borrow any more money from Linda.
B. Nancy advised Linda not to lend Susan any more money.
C. Linda advised Susan not to lend Linda any more money.
D. Nancy advised Linda to lend Susan some more money.
1.a
2.c
3.a
4.b
5.c
6.a
7.c
8.b
Cho mình sorry.
1.b mới đúng!!!