Danh sách câu hỏi

Có 50,580 câu hỏi trên 1,012 trang
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.Continents and ocean basins represent the largest identifiable bodies on Earth. On the solid portions of the planet, the second most prominent features are flat plains, elevated plateaus, and large mountain ranges. In geography, the term "continent" refers to the surface of continuous landmasses that together comprise about 29.2% of the planet's surface. On the other hand, another definition is prevalent in the general use of the term that deals with    extensive main lands, such as Europe or Asia, that actually represent one very large landmass. Although all continents are bounded by the water bodies or high mountain ranges, isolated main lands, such as Greenland and India-Pakistan areas are called subcontinents. In some circles, the distinction between continents and large islands lies almost exclusively in the size of a particular landmass.The analysis of compression and tension in the earth's crust has determined that continental structures are composed of layers that underlie continental shelves. A great deal of disagreement among geologists surrounds the issue of exactly how many layers underlie each landmass because of their distinctive mineral and chemical composition. It's also quite possible that the ocean floor rests on top of unknown continents that have not yet been explored. The continental crust is believed to have been formed by means of a chemical reaction when lighter materials separated from heavier ones, thus settling at various levels within the crust. Assisted by the measurements of the specifics within crust formations by means of monitoring earthquakes, geologists can speculate that a chemical split occurred to form the atmosphere, sea water and the crust before it solidified many centuries ago.Although each continent has its special features, all consist of various combinations of components that include shields, mountain belts, intra - cratonic basins, margins, volcanic plateaus, and block-vaulted belts. The basic differences among continents lie in the proportion and the composition of these features relative to the continent size. Climatic zones have a crucial effect on the weathering and formation of the surface features, soil erosion, soil deposition, land formation, vegetation, and human activities.Mountain belts are elongated narrow zones that have a characteristic folded sedimentary organization of layers. They are typically produced during substantial crustal movements, which generate faulting and mountain building. When continental margins collide, the rise of a marginal edge leads to the formation of large mountain ranges, as explained by the plate tectonic theory. This process also accounts for the occurrence of mountain belts in ocean basins and produces evidence for the ongoing continental plate evolution.The author in the passage implies that the disagreement among scientists is based on the fact that 
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.Continents and ocean basins represent the largest identifiable bodies on Earth. On the solid portions of the planet, the second most prominent features are flat plains, elevated plateaus, and large mountain ranges. In geography, the term "continent" refers to the surface of continuous landmasses that together comprise about 29.2% of the planet's surface. On the other hand, another definition is prevalent in the general use of the term that deals with    extensive main lands, such as Europe or Asia, that actually represent one very large landmass. Although all continents are bounded by the water bodies or high mountain ranges, isolated main lands, such as Greenland and India-Pakistan areas are called subcontinents. In some circles, the distinction between continents and large islands lies almost exclusively in the size of a particular landmass.The analysis of compression and tension in the earth's crust has determined that continental structures are composed of layers that underlie continental shelves. A great deal of disagreement among geologists surrounds the issue of exactly how many layers underlie each landmass because of their distinctive mineral and chemical composition. It's also quite possible that the ocean floor rests on top of unknown continents that have not yet been explored. The continental crust is believed to have been formed by means of a chemical reaction when lighter materials separated from heavier ones, thus settling at various levels within the crust. Assisted by the measurements of the specifics within crust formations by means of monitoring earthquakes, geologists can speculate that a chemical split occurred to form the atmosphere, sea water and the crust before it solidified many centuries ago.Although each continent has its special features, all consist of various combinations of components that include shields, mountain belts, intra - cratonic basins, margins, volcanic plateaus, and block-vaulted belts. The basic differences among continents lie in the proportion and the composition of these features relative to the continent size. Climatic zones have a crucial effect on the weathering and formation of the surface features, soil erosion, soil deposition, land formation, vegetation, and human activities.Mountain belts are elongated narrow zones that have a characteristic folded sedimentary organization of layers. They are typically produced during substantial crustal movements, which generate faulting and mountain building. When continental margins collide, the rise of a marginal edge leads to the formation of large mountain ranges, as explained by the plate tectonic theory. This process also accounts for the occurrence of mountain belts in ocean basins and produces evidence for the ongoing continental plate evolution.The word "bounded" is closest in meaning to    
 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. Continents and ocean basins represent the largest identifiable bodies on Earth. On the solid portions of the planet, the second most prominent features are flat plains, elevated plateaus, and large mountain ranges. In geography, the term "continent" refers to the surface of continuous landmasses that together comprise about 29.2% of the planet's surface. On the other hand, another definition is prevalent in the general use of the term that deals with    extensive main lands, such as Europe or Asia, that actually represent one very large landmass. Although all continents are bounded by the water bodies or high mountain ranges, isolated main lands, such as Greenland and India-Pakistan areas are called subcontinents. In some circles, the distinction between continents and large islands lies almost exclusively in the size of a particular landmass.The analysis of compression and tension in the earth's crust has determined that continental structures are composed of layers that underlie continental shelves. A great deal of disagreement among geologists surrounds the issue of exactly how many layers underlie each landmass because of their distinctive mineral and chemical composition. It's also quite possible that the ocean floor rests on top of unknown continents that have not yet been explored. The continental crust is believed to have been formed by means of a chemical reaction when lighter materials separated from heavier ones, thus settling at various levels within the crust. Assisted by the measurements of the specifics within crust formations by means of monitoring earthquakes, geologists can speculate that a chemical split occurred to form the atmosphere, sea water and the crust before it solidified many centuries ago.Although each continent has its special features, all consist of various combinations of components that include shields, mountain belts, intra - cratonic basins, margins, volcanic plateaus, and block-vaulted belts. The basic differences among continents lie in the proportion and the composition of these features relative to the continent size. Climatic zones have a crucial effect on the weathering and formation of the surface features, soil erosion, soil deposition, land formation, vegetation, and human activities.Mountain belts are elongated narrow zones that have a characteristic folded sedimentary organization of layers. They are typically produced during substantial crustal movements, which generate faulting and mountain building. When continental margins collide, the rise of a marginal edge leads to the formation of large mountain ranges, as explained by the plate tectonic theory. This process also accounts for the occurrence of mountain belts in ocean basins and produces evidence for the ongoing continental plate evolution.According to the passage, how do scientists define continents? 
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.Continents and ocean basins represent the largest identifiable bodies on Earth. On the solid portions of the planet, the second most prominent features are flat plains, elevated plateaus, and large mountain ranges. In geography, the term "continent" refers to the surface of continuous landmasses that together comprise about 29.2% of the planet's surface. On the other hand, another definition is prevalent in the general use of the term that deals with    extensive main lands, such as Europe or Asia, that actually represent one very large landmass. Although all continents are bounded by the water bodies or high mountain ranges, isolated main lands, such as Greenland and India-Pakistan areas are called subcontinents. In some circles, the distinction between continents and large islands lies almost exclusively in the size of a particular landmass.The analysis of compression and tension in the earth's crust has determined that continental structures are composed of layers that underlie continental shelves. A great deal of disagreement among geologists surrounds the issue of exactly how many layers underlie each landmass because of their distinctive mineral and chemical composition. It's also quite possible that the ocean floor rests on top of unknown continents that have not yet been explored. The continental crust is believed to have been formed by means of a chemical reaction when lighter materials separated from heavier ones, thus settling at various levels within the crust. Assisted by the measurements of the specifics within crust formations by means of monitoring earthquakes, geologists can speculate that a chemical split occurred to form the atmosphere, sea water and the crust before it solidified many centuries ago.Although each continent has its special features, all consist of various combinations of components that include shields, mountain belts, intra - cratonic basins, margins, volcanic plateaus, and block-vaulted belts. The basic differences among continents lie in the proportion and the composition of these features relative to the continent size. Climatic zones have a crucial effect on the weathering and formation of the surface features, soil erosion, soil deposition, land formation, vegetation, and human activities.Mountain belts are elongated narrow zones that have a characteristic folded sedimentary organization of layers. They are typically produced during substantial crustal movements, which generate faulting and mountain building. When continental margins collide, the rise of a marginal edge leads to the formation of large mountain ranges, as explained by the plate tectonic theory. This process also accounts for the occurrence of mountain belts in ocean basins and produces evidence for the ongoing continental plate evolution.What does this passage mainly discuss?
Read the followingpassage and mark the letter A, B, C or D onyour answer sheet to indicate the correct answer to each of the questionsStellar AstronomyMany parameters are used to describe a star. One of them is its temperature, which can be determined by simple observation; the color of a star and its temperature are related. Once the color of a star is identified, its temperature can be calculated through the use of scientific principles such as Wien’s Law.There are different types of stars in the universe. For our purposes, we can classify them into two categories: variable and binary. Variable stars are those which show some degree of variability in their luminosity and magnitude. Luminosity refers to the amount of energy radiated by a star, while magnitude refers to its brightness. At time the degree of variability may be high, requiring a telescope with an equally high light- gathering power. This can be achieved by using a lens of large diameter, such as that of a reflecting telescope.Binary stars are those found in pairs that revolve around a common center. The closest star to the sun, Proxima Centauri, is a binary star. To observe a binary star, the resolving power of a telescope - its ability to distinguish between two close objects having a small angular separation - must be very high.Stellar astronomy is possible for a everyone, well beyond mere looking at the sky with the naked eye in order to identify constellations. With two basic of telescopes and rudimentary knowledge, much exploration can be achieved.Why does the author write that “stellar astronomy is possible for everyone”?
Read the followingpassage and mark the letter A, B, C or D onyour answer sheet to indicate the correct answer to each of the questionsStellar AstronomyMany parameters are used to describe a star. One of them is its temperature, which can be determined by simple observation; the color of a star and its temperature are related. Once the color of a star is identified, its temperature can be calculated through the use of scientific principles such as Wien’s Law.There are different types of stars in the universe. For our purposes, we can classify them into two categories: variable and binary. Variable stars are those which show some degree of variability in their luminosity and magnitude. Luminosity refers to the amount of energy radiated by a star, while magnitude refers to its brightness. At time the degree of variability may be high, requiring a telescope with an equally high light- gathering power. This can be achieved by using a lens of large diameter, such as that of a reflecting telescope.Binary stars are those found in pairs that revolve around a common center. The closest star to the sun, Proxima Centauri, is a binary star. To observe a binary star, the resolving power of a telescope - its ability to distinguish between two close objects having a small angular separation - must be very high.Stellar astronomy is possible for a everyone, well beyond mere looking at the sky with the naked eye in order to identify constellations. With two basic of telescopes and rudimentary knowledge, much exploration can be achieved.Which of the following is true of variable stars?
Read the followingpassage and mark the letter A, B, C or D onyour answer sheet to indicate the correct answer to each of the questionsStellar AstronomyMany parameters are used to describe a star. One of them is its temperature, which can be determined by simple observation; the color of a star and its temperature are related. Once the color of a star is identified, its temperature can be calculated through the use of scientific principles such as Wien’s Law.There are different types of stars in the universe. For our purposes, we can classify them into two categories: variable and binary. Variable stars are those which show some degree of variability in their luminosity and magnitude. Luminosity refers to the amount of energy radiated by a star, while magnitude refers to its brightness. At time the degree of variability may be high, requiring a telescope with an equally high light- gathering power. This can be achieved by using a lens of large diameter, such as that of a reflecting telescope.Binary stars are those found in pairs that revolve around a common center. The closest star to the sun, Proxima Centauri, is a binary star. To observe a binary star, the resolving power of a telescope - its ability to distinguish between two close objects having a small angular separation - must be very high.Stellar astronomy is possible for a everyone, well beyond mere looking at the sky with the naked eye in order to identify constellations. With two basic of telescopes and rudimentary knowledge, much exploration can be achieved.The temperature of a star can be determined by its
Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life, it appears permanent and unchanging, save for the season growth and fall of the leaves, but to the forester, it represents the climax of a long succession of events.No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth’s surface has, at some time, been either too dry or too cool for plants to survive.However, as soon as climatic conditions change in favor of plant life, a fascinating sequence of changes, called a primary succession, occurs first to colonize the barren land and the lichen surviving on bare rock. Slowly, the acids produced by these organisms crack the rock’s surface, plants debris accumulate and mosses establish shallow root-holes. Ferns may allow and, with short grasses and shrubs, gradually form a covering of plant life. Roots broke even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination - closing their ranks and forming a climax community which may endure for thousands of years. Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivations. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and lodged in the coat of mammals.For as long as it stands and strives, the forest is a vast machine storing energy and the many elements essential for life.What has sometimes caused plants to die out in the past?
Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life, it appears permanent and unchanging, save for the season growth and fall of the leaves, but to the forester, it represents the climax of a long succession of events.No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth’s surface has, at some time, been either too dry or too cool for plants to survive.However, as soon as climatic conditions change in favor of plant life, a fascinating sequence of changes, called a primary succession, occurs first to colonize the barren land and the lichen surviving on bare rock. Slowly, the acids produced by these organisms crack the rock’s surface, plants debris accumulate and mosses establish shallow root-holes. Ferns may allow and, with short grasses and shrubs, gradually form a covering of plant life. Roots broke even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination - closing their ranks and forming a climax community which may endure for thousands of years. Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivations. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and lodged in the coat of mammals.For as long as it stands and strives, the forest is a vast machine storing energy and the many elements essential for life.What conditions are needed for shrubs to become established?
Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life, it appears permanent and unchanging, save for the season growth and fall of the leaves, but to the forester, it represents the climax of a long succession of events.No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth’s surface has, at some time, been either too dry or too cool for plants to survive.However, as soon as climatic conditions change in favor of plant life, a fascinating sequence of changes, called a primary succession, occurs first to colonize the barren land and the lichen surviving on bare rock. Slowly, the acids produced by these organisms crack the rock’s surface, plants debris accumulate and mosses establish shallow root-holes. Ferns may allow and, with short grasses and shrubs, gradually form a covering of plant life. Roots broke even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination - closing their ranks and forming a climax community which may endure for thousands of years. Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivations. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and lodged in the coat of mammals.For as long as it stands and strives, the forest is a vast machine storing energy and the many elements essential for life.Why do we tend to think the forest as permanent?