Choose the best answer for the following sentence:

She is absent __________ class.

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 43 to 50:

Smallpox was the first widespread disease to be eliminated by human intervention. Known as a highly contagious viral disease, it broke out in Europe, causing the deaths of millions of people until the vaccination was invented by Edward Jenner around 1800. In many nations, it was a terror, a fatal disease until very recently. Its victims suffer high fever, vomiting and painful, itchy, pustules that left scars. In villages and cities all over the world, people were worried about suffering smallpox.In May, 1966, the World Health Organization (WHO), an agency of the United Nations was authorized to initiate a global campaign to eradicate smallpox. The goal was to eliminate the disease in one decade. At the time, the disease posed a serious threat to people in more than thirty nations. Because similar projects for malaria and yellow fever had failed, few believed that smallpox could actually be eradicated but eleven years after the initial organization of the campaign, no cases were reported in the field.The strategy was not only to provide mass vaccinations but also to isolate patients with active smallpox in order to contain the spread of the disease and to break the chain of human transmission. Rewards for reporting smallpox assisted in motivating the public to aid health workers. One by one, each small-pox victim was sought out, removed from contact with others and treated. At the same time, the entire village where the victim had lived was vaccinated.By April of 1978 WHO officials announced that they had isolated the last known case of the disease but health workers continued to search for new cases for additional years to be completely sure. In May, 1980, a formal statement was made to the global community. Today smallpox is no longer a threat to humanity. Routine vaccinations have been stopped worldwide.  

Question 46: The word “threat” in paragraph 2 could best be replaced by ___________.         

Một hệ dao động cơ đang thực hiện dao động cưỡng bức. Hiện tượng cộng hưởng xảy ra khi:

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 43 to 50:

Smallpox was the first widespread disease to be eliminated by human intervention. Known as a highly contagious viral disease, it broke out in Europe, causing the deaths of millions of people until the vaccination was invented by Edward Jenner around 1800. In many nations, it was a terror, a fatal disease until very recently. Its victims suffer high fever, vomiting and painful, itchy, pustules that left scars. In villages and cities all over the world, people were worried about suffering smallpox.In May, 1966, the World Health Organization (WHO), an agency of the United Nations was authorized to initiate a global campaign to eradicate smallpox. The goal was to eliminate the disease in one decade. At the time, the disease posed a serious threat to people in more than thirty nations. Because similar projects for malaria and yellow fever had failed, few believed that smallpox could actually be eradicated but eleven years after the initial organization of the campaign, no cases were reported in the field.The strategy was not only to provide mass vaccinations but also to isolate patients with active smallpox in order to contain the spread of the disease and to break the chain of human transmission. Rewards for reporting smallpox assisted in motivating the public to aid health workers. One by one, each small-pox victim was sought out, removed from contact with others and treated. At the same time, the entire village where the victim had lived was vaccinated.By April of 1978 WHO officials announced that they had isolated the last known case of the disease but health workers continued to search for new cases for additional years to be completely sure. In May, 1980, a formal statement was made to the global community. Today smallpox is no longer a threat to humanity. Routine vaccinations have been stopped worldwide.  

Question 43: Which of the following is the best title for the passage?  

Trong dao động cơ học, khi nói về vật dao động cưỡng bức (giai đoạn đã ổn định), phát biểu nào sau đây là đúng?

Khi nói về dao động cơ tắt dần của một vật, phát biểu nào sau đây đúng?

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 43 to 50:

Smallpox was the first widespread disease to be eliminated by human intervention. Known as a highly contagious viral disease, it broke out in Europe, causing the deaths of millions of people until the vaccination was invented by Edward Jenner around 1800. In many nations, it was a terror, a fatal disease until very recently. Its victims suffer high fever, vomiting and painful, itchy, pustules that left scars. In villages and cities all over the world, people were worried about suffering smallpox.In May, 1966, the World Health Organization (WHO), an agency of the United Nations was authorized to initiate a global campaign to eradicate smallpox. The goal was to eliminate the disease in one decade. At the time, the disease posed a serious threat to people in more than thirty nations. Because similar projects for malaria and yellow fever had failed, few believed that smallpox could actually be eradicated but eleven years after the initial organization of the campaign, no cases were reported in the field.The strategy was not only to provide mass vaccinations but also to isolate patients with active smallpox in order to contain the spread of the disease and to break the chain of human transmission. Rewards for reporting smallpox assisted in motivating the public to aid health workers. One by one, each small-pox victim was sought out, removed from contact with others and treated. At the same time, the entire village where the victim had lived was vaccinated.By April of 1978 WHO officials announced that they had isolated the last known case of the disease but health workers continued to search for new cases for additional years to be completely sure. In May, 1980, a formal statement was made to the global community. Today smallpox is no longer a threat to humanity. Routine vaccinations have been stopped worldwide.  

 Question 44: The word “contagious” is closest in meaning to ___________.         

Khi xảy ra cộng hưởng cơ thì vật tiếp tục dao động:

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answers:

All mammals feed their young. Beluga whale mothers, for example, nurse their calves for some twenty months, until they are about to give birth again and their young are able to find their own food. The behavior of feeding of the young is built into the reproductive system. It is a nonelective part of parental care and the defining feature of a mammal, the most important thing that mammals - whether marsupials, platypuses, spiny anteaters, or placental mammals - have in common.

For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal's life is when it first finds itself completely on its own, when it must forage and fend for itself. Feeding postpones that moment until a young animal has grown to such a size that it is better able to cope. Young that are fed by their parents become nutritionally independent at a much greater fraction of their full adult size. And in the meantime those young are shielded against the vagaries of fluctuating of difficult-to-find supplies. Once a species does take the step of feeding its young, the young become totally dependent on the extra effort. If both parents are removed, the young generally do not survive.

Question: The word "shielded" in the last paragraph is closest in meaning to _______.             

Một người xách một xô nước đi trên đường, mỗi bước đi được 50 cm. Chu kỳ dao động riêng của nước trong xô là 1 s. Nước trong xô sóng sánh mạnh nhất khi người đó đi với vận tốc.

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answers:

All mammals feed their young. Beluga whale mothers, for example, nurse their calves for some twenty months, until they are about to give birth again and their young are able to find their own food. The behavior of feeding of the young is built into the reproductive system. It is a nonelective part of parental care and the defining feature of a mammal, the most important thing that mammals - whether marsupials, platypuses, spiny anteaters, or placental mammals - have in common.

For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal's life is when it first finds itself completely on its own, when it must forage and fend for itself. Feeding postpones that moment until a young animal has grown to such a size that it is better able to cope. Young that are fed by their parents become nutritionally independent at a much greater fraction of their full adult size. And in the meantime those young are shielded against the vagaries of fluctuating of difficult-to-find supplies. Once a species does take the step of feeding its young, the young become totally dependent on the extra effort. If both parents are removed, the young generally do not survive.

Question: The word "it" in the third paragraph refers to _______.