Với giá trị nào của m thì hệ $\left\{\begin{array}{c}-x+2y+z=1\\ -x+y+2z=3\\ 2x-5y+mz=1\end{array}\right.$ có nghiệm

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:

Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a drive made with scuba gear because the breathing equipment allows divers to stay underwater longer and dive deeper. The pressure exerted on the human body increases by 1 atmosphere for every 10 meters of depth on seater, so thay at 39 meters in seawater a diver is exposed to pressure of about 4 atmosphere. The pressure of the gases being breathed must equal the external pressure applied to the body, otherwise breathing is very difficult. Therefore all of the gases in the air breathed by a scuba diver at 40 meter are present at five times their usual pressure. Nitrogen, which composes 80 percent of the air we breathe, usually causes a balmy feeling of well-being at this pressure. At a depth of 5 atmosphere, nitrogen causes symptoms resembling alcohol intoxication, known as nitrogen narcosis. Nitrogen narcosis apparently results from a direct effect on the brain of the large amounts of nitrogen dissolved in the blood. Deep dives are less dangerous if helium is substituted for nitrogen, because under these pressures helium does not exert a similar narcotic effect. As a scuba diver descends, the pressure of nitrogen on the lungs increases. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues. The reverse occurs when the diver surfaces, the nitrogen pressure in the lungs falls and the nitrogen diffuses from the tissues into the blood, and from the blood into the lungs. If the return to the surface is too rapid, nitrogen in the tissues and blood cannot diffuse out rapidly enough and nitrogen bubbles are formed. They can cause severe pains, particularly around the joints. Another complication may result if the breath is held during ascent. During ascent from a depth of 10 meters, the volume of air in the lungs will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend ang even rupture. This the rise of the exhaled air bubbles, and must exhale during ascent.

Question: What happens to nitrogen in body tissues if a diver ascends too quickly?         

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions:

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning.

This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university.

When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college.

Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors.

Question: The passage indicates that Harvard is ____________.        

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions:

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning.

This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university.

When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college.

Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors.

Question: It can be inferred from the passage that the Puritans who traveled to the Massachusetts colony were ______________.         

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following question.

If_____, the Xmas tree would look more impressive.         

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning. This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university. When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college. Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors.

The main idea of this passage is that ______________ .         

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions:

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning.

This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university.

When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college.

Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors.

Question: The pronoun "they" in the second paragraph refers to ____________.         

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions:

Harvard University, today recognized as part of the top echelon of the world's universities, came from very inauspicious and humble beginning.

This oldest of American universities was founded in 1636, just sixteen years after the Pilgrims landed at Plymouth. Included in the Puritan emigrants to the Massachusetts colony during this period were more than 100 graduates of England's prestigious Oxford and Cambridge universities, and these universities graduates in the New Word were determined that their sons would have the same educational opportunities that they themselves had had. Because of this support in the colony for an institution of higher learning, the General Court of Massachusetts appropriated 400 pounds for a college in October of 1636 and early the following year decided on a parcel of land for the school; this land was in an area called Newetowne, which was later renamed Cambridge after its English cousin and is the site of the present-day university.

When a young minister named John Harvard, who came from the neighboring town of Charlestowne, died from tuberculosis in 1638, he willed half of his estate of 1,700 pounds to the fledgling college. In spite of the fact that only half of the bequest was actually paid, the General Court named the college after the minister in appreciation for what he had done. The amount of the bequest may not have been large, particularly by today's standard, but it was more than the General Court had found it necessary to appropriate in order to open the college.

Henry Dunster was appointed the first president of Harvard in 1640, and it should be noted that in addition to serving as president, he was also the entire faculty, with an entering freshmen class of four students. Although the staff did expand somewhat, for the first century of its existence the entire teaching staff consisted of the president and three or four tutors.

Question: The "pounds" in the second paragraph are probably ___________.       

Read the following passage and mark the letters A, B, C or D on your answer sheet to indicate the correct answer to each of the questions: 

This rapid transcontinental settlement and these new urban industrial circumstances of the last half of the 19th century were accompanied by the development of national literature of great abundance and variety. New themes, new forms, new subjects, new regions, new authors, new audiences all emerged in the literature of this half century.

As a result, at the onset of World War I, the spirit and substance of American literature had evolved remarkably, just as its center of production had shifted from Boston to New York in the late 1880s and the sources of its energy to Chicago and the Midwest. No longer was it produced, at least in its popular forms, in the main by solemn, typically moralistic men from New England and the Old South; no longer were polite, well-dressed, grammatically correct, middle-class young people the only central characters in its narratives; no longer were these narratives to be set in exotic places and remote times; no longer, indeed, were fiction, poetry, drama, and formal history the chief acceptable forms of literary expression; no longer, finally, was literature read primarily by young, middle class women.

In sum, American literature in these years fulfilled in considerable measure the condition Walt Whitman called for in 1867 in describing Leaves of Grass: it treats, he said of his own major work, each state and region as peers "and expands from them, and includes the world ... connecting an American citizen with the citizens of all nations." At the same time, these years saw the emergence of what has been designated "the literature of argument," powerful works in sociology, philosophy, psychology, many of them impelled by the spirit of exposure and reform. Just as America learned to play a role in this half century as an autonomous international political, economic, and military power, so did its literature establish itself as a producer of major works.

Question: It can be inferred from the passage that Walt Whitman________.               

Read the following passage on climate change, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

One day in 1924, five men who were camping in the Cascade Mountains of Washington saw a group of huge apelike creatures coming out of the woods. They hurried back to their cabin and locked themselves inside. While they were in, the creatures attacked them by throwing rocks against the walls of the cabin.After several hours, these strange hairy giants went back into the woods.

After this incident the men returned to the town and told the people of their adventure. However, only a few people accepted their story. These were the people who remembered hearing tales about footprints of an animal that walked like a human being.

The five men, however, were not the first people to have seen these creatures called Bigfoot. Long before their experience, local Native Americans were certain that a race of apelike animals had been living in the neighboring mountain for centuries. They called these creatures Sasquatch.

In 1958, workmen, who were building a road through the jungles of Northern California often found huge footprints in the earth around their camp.

Then in 1967, Roger Patterson, a man who was interested in finding Bigfoot went into the Northern California jungles with a friend. While riding, they were suddenly thrown off from their horses. Patterson saw a tall apelike animal standing not far away. He managed to shoot seven rolls of film of the hairy creature before the animal disappeared in the hushes. when Patterson's film was shown to the public, not many people believed his story. In another incident, Richard Brown, a music teacher and also an experienced hunter spotted a similar creature. He saw the animal clearly through the telescopic lens of his rifle. He said the creature looked more like a human than an animal.

Later many other people also found deep footprints in the same area. In spite of regular reports of sightings and footprints, most experts still do not believe that Bigfoot really exists.

Question: Who were the first people to have seen these apelike creatures before the five campers?         

Read the following passage on climate change, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

One day in 1924, five men who were camping in the Cascade Mountains of Washington saw a group of huge apelike creatures coming out of the woods. They hurried back to their cabin and locked themselves inside. While they were in, the creatures attacked them by throwing rocks against the walls of the cabin.After several hours, these strange hairy giants went back into the woods.

After this incident the men returned to the town and told the people of their adventure. However, only a few people accepted their story. These were the people who remembered hearing tales about footprints of an animal that walked like a human being.

The five men, however, were not the first people to have seen these creatures called Bigfoot. Long before their experience, local Native Americans were certain that a race of apelike animals had been living in the neighboring mountain for centuries. They called these creatures Sasquatch.

In 1958, workmen, who were building a road through the jungles of Northern California often found huge footprints in the earth around their camp.

Then in 1967, Roger Patterson, a man who was interested in finding Bigfoot went into the Northern California jungles with a friend. While riding, they were suddenly thrown off from their horses. Patterson saw a tall apelike animal standing not far away. He managed to shoot seven rolls of film of the hairy creature before the animal disappeared in the hushes. when Patterson's film was shown to the public, not many people believed his story. In another incident, Richard Brown, a music teacher and also an experienced hunter spotted a similar creature. He saw the animal clearly through the telescopic lens of his rifle. He said the creature looked more like a human than an animal.

Later many other people also found deep footprints in the same area. In spite of regular reports of sightings and footprints, most experts still do not believe that Bigfoot really exists.

 Question: The BEST title for this passage would be_________.