Số “mười chín” được viết thành số La Mã là:

A. XXI

B. IXX

C. XIX

Tính bằng cách thuận tiện nhất:

8,99  × 89,9 – 19,5  × 8,99 + 8,99  × 29,6 = 

Cho hình bình hành ABCD. Gọi E là điểm đối xứng với D qua A, F là điểm đối xứng với D qua C. Chứng minh: Điểm E đối xứng với điểm F qua điểm B.

a. Tính bằng cách thuận tiện: 4,83 x 8,9 – 4,83 x 7,9

b. Tìm x: 2 : x = 12,5

Khi lực đẩy Ác-si-mét lớn hơn trọng lượng vật thì:

A. Vật chìm xuống

B. Vật nổi lên

C. Vật lơ lửng trong chất lỏng

D. Vật chìm xuống đáy chất lỏng

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

Researchers in the field of psychology have found that one of the best way to make an important decision, such as choosing a university to attend or business to invest in, involves the utilization of a decision worksheet. Psychologists who study optimization compare the actual decisions made by people to theretical ideal decisions to see how similar they are. Proponents of the worksheet procedure believe that it will yield optimal , that is, the best decisions. Although there are several variations on the exact format that worksheets cam take, they are all similar in their essential aspects.

Worksheets require defining the problem in a clear and concise way and then listing all possible solutions to the problem. Next, the pertinent considerations that all possible solutions to the problem. Next, the pertinent considerations that will be affected by each decision are listed, and the relative importance of each consideration or consequence is determined. Each consideration is assigned a numerical value to reflect its relative importance. A decision is mathematically calculated by adding these values together. The alternative with the highest number of points emerges as the best decision.

Since most important problems are multifaceted, there are several alternatives to choose from, each with unique advantages and disadvantages. One of the benefits of a pencil and paper decision-making procedure is that it permits people to deal with more variables than their minds can generally comprehend and remember. On the average, people can keep about seven ideas in their minds at once. A worksheet can be especially useful when the decision involves a large number of variables with complex relationships. A realistic example for many college students is the question "What will I do after graduation?" A graduate might seek a position that offers specialized training, pursue an advanced degree, or travel abroad for a year.

A decision-making worksheet begins with a succinct statement of the problem that will also help to narrow it. It is important to be clear about the distinction between long-range and immediate goals because long-range goals often involve a different decision than short-range ones. Focusing on long-range goals, a graduating student might revise the question above to "What will I do after graduation that will lead to a successful career?"

Which of the following terms is defined in the passage?

A. Proponents (para. 1)

B. Optimal (para. 1)

C. Variables (para. 3)

D. Long-range goals (para. 4)

Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely . Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. Theseserve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

Which of the following is best supported by the passage?

A. To effectively control pollution local government should regularly review their air pollution laws.

B. One of the most important steps in preserving natural lands is to better enforce air pollution laws.

C. Scientists should be consulted in order to establish uniform limits for all air pollutants.

D. Human activities have been effective in reducing air pollution.

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.

Reading to oneself is a modern activity which was almost unknown to the scholars of the classical and medieval worlds, while during the fifteenth century the term “reading” undoubtedly meant reading aloud. Only during the nineteenth century did silent reading become commonplace.

One should be wary, however, of assuming that silent reading came about simply because reading aloud was a distraction to others. Examinations of factors related to the historical development of silent reading have revealed that it became the usual mode of reading for most adults mainly because the tasks themselves changed in character.

The last century saw a steady gradual increase in literacy and thus in the number of readers. As the number of readers increased, the number of potential listeners declined and thus there was some reduction in the need to read aloud. As reading for the benefit of listeners grew less common, came the flourishing of reading as a private activity in such public places as libraries, railway carriages and offices, where reading aloud would cause distraction to other readers.

Towards the end of the century, there was still considerable argument over whether books should be used for information or treated respectfully and over whether the reading of materials such as newspapers was in some way mentally weakening. Indeed, this argument remains with us still in education. However, whatever its virtues, the old shared literacy culture had gone and were replaced by the printed mass media on the one hand and by books and periodicals for a specialized readership on the other.

By the end of the twentieth century, students were being recommended to adopt attitudes to books and to use reading skills which were inappropriate, if not impossible, for the oral reader. The social, cultural and technological changes in the century had greatly altered what the term “reading” implied

Question: The writer of this passage is attempting to_________.

A. change people’s attitudes to reading

B. explain how reading habits have developed

C. encourage the growth of reading

D. show how reading methods have improved

Diện tích hình phẳng giới hạn bởi các đường y = x 4 ,   y = − x 2   v à   x = 1  là

A.  8 15 .

B.  2 15 .

C.  1 4 .

D. 1

Cho hàm số f x = x + a      khi x < 0 x 2 + 1     khi x ≥ 0 .  Xác định a để hàm số liên tục tại x 0 = 0 .  

A. a = 0

B. a = 2

C. a = –1

D. a = 1