Xét một locus gồm 2 alen (A và a). Tần số alen a ở thế hệ xuất phát =38%. Qua mỗi thế hệ, đột biến làm cho a chuyển thành A với tần số 10%. Sau 3 thế hệ thì tần số A của quần thể bằng

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks:

Many animals in the wild are suspicious and fearful of human beings. Many animals would take flight instantly (31)______ a human approaches. Man, however, soon discovered that some animals can be tamed or domesticated. Unlike animals in the wild, these animals would (32) _______ man to come close to them. They would even allow their owners to stroke or pet them. In the early times, man would domesticate animals by setting traps to catch their young. A young animal is (33) _______ easily domesticated than an adult one. From young, the animal learns to trust and obey its owner. Many different kinds of animals have been domesticated. Some common examples are animals like horses, elephants, chickens and pigs. The dog, which is also (34) _______as “man’s best friend”, is one of the first animals to have been domesticated. One of the most unusual animals to have been domesticated is the pig. In England long ago, the pig was a wild animal. It was a ferocious and aggressive (35)_______ which was not easily captured. Yet nowadays, the domesticated pig is no longer the lean and tough creature it used to be.  

Question 35:

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35:

Some years ago, my daughter was studying English at a university on the south coast. One evening she phoned to tell me that what she really wanted to do was looking (31) ________the world, so she was looking into the possibility of working in another country. She had seen several (32) ________ in the newspaper for student teachers of English abroad, and she was interested in one in Italy, which she was desperate to visit. She decided that this would be a good way to achieve her ambition, so she was writing to apply for the job. The reply took a long time to arrive, but eventually she received a letter asking if she would go for an interview in London the following week. She was so excited that she immediately got in touch with the school owner and agreed to attend the interview. She was determined that nothing would prevent her (33) ________ doing what she had set out to do. A few days before the interview she had a very strange dream in which she gave birth to a beautiful baby. She was a little nervous and (34) ________about the dream and phoned to ask me what I thought it might mean. As I knew something about dreams, I was able to assure her that it only symbolized her (35) ________to do well in the interview. 

Question 31:

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35:

Some years ago, my daughter was studying English at a university on the south coast. One evening she phoned to tell me that what she really wanted to do was looking (31) ________the world, so she was looking into the possibility of working in another country. She had seen several (32) ________ in the newspaper for student teachers of English abroad, and she was interested in one in Italy, which she was desperate to visit. She decided that this would be a good way to achieve her ambition, so she was writing to apply for the job. The reply took a long time to arrive, but eventually she received a letter asking if she would go for an interview in London the following week. She was so excited that she immediately got in touch with the school owner and agreed to attend the interview. She was determined that nothing would prevent her (33) ________ doing what she had set out to do. A few days before the interview she had a very strange dream in which she gave birth to a beautiful baby. She was a little nervous and (34) ________about the dream and phoned to ask me what I thought it might mean. As I knew something about dreams, I was able to assure her that it only symbolized her (35) ________to do well in the interview. 

Question 32: 

Read the following passage and mark the letter A, B, C or D to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35:                                                                  

                                                                       SCHOOL LUNCH

Research has shown that over half the children in Britain who take their own lunches to school do not eat (31) _______ in the middle of the day. In Britain, schools have to provide meals at lunchtime. Children can choose to bring their own food or have lunch at the school canteen. One shocking (32) _______ of this research is that school meals are much healthier than lunches prepared by parents. There are strict standards for the preparation of school meals, which have to include one portion of fruit and one of vegetables, as well as meat, a dairy item and starchy food like bread or pasta. Lunchboxes (33) _______ by researchers contained sweet drinks, crisps and chocolate bars. Children (34) _______ twice as much sugar as they should at lunchtime. The reseat will provide a better understanding of why the percentage of overweight students in Britain has increased in the last decade. Unfortunately, the government cannot instruct parents, but it can remind them of the (35) _______ value of milk, fruit and vegetables. Children can easily develop bad eating habits at this age, and parents are the only ones who can prevent it.

Question 31:

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35:                                                                                                                        

                                                                SCHOOL LUNCH

Research has shown that over half the children in Britain who take their own lunches to school do not eat (31) _______ in the middle of the day. In Britain, schools have to provide meals at lunchtime. Children can choose to bring their own food or have lunch at the school canteen. One shocking (32) _______ of this research is that school meals are much healthier than lunches prepared by parents. There are strict standards for the preparation of school meals, which have to include one portion of fruit and one of vegetables, as well as meat, a dairy item and starchy food like bread or pasta. Lunchboxes (33) _______ by researchers contained sweet drinks, crisps and chocolate bars. Children (34) _______ twice as much sugar as they should at lunchtime. The reseat will provide a better understanding of why the percentage of overweight students in Britain has increased in the last decade. Unfortunately, the government cannot instruct parents, but it can remind them of the (35) _______ value of milk, fruit and vegetables. Children can easily develop bad eating habits at this age, and parents are the only ones who can prevent it.

Question 33:

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35:                                                                  

                                                                  SCHOOL LUNCH

Research has shown that over half the children in Britain who take their own lunches to school do not eat (31) _______ in the middle of the day. In Britain, schools have to provide meals at lunchtime. Children can choose to bring their own food or have lunch at the school canteen. One shocking (32) _______ of this research is that school meals are much healthier than lunches prepared by parents. There are strict standards for the preparation of school meals, which have to include one portion of fruit and one of vegetables, as well as meat, a dairy item and starchy food like bread or pasta. Lunchboxes (33) _______ by researchers contained sweet drinks, crisps and chocolate bars. Children (34) _______ twice as much sugar as they should at lunchtime. The reseat will provide a better understanding of why the percentage of overweight students in Britain has increased in the last decade. Unfortunately, the government cannot instruct parents, but it can remind them of the (35) _______ value of milk, fruit and vegetables. Children can easily develop bad eating habits at this age, and parents are the only ones who can prevent it.

Question 32:

Choose the word or phrase (A, B, C or D) that best fits the blank space in the following passage:

                                                                                     PAPER

'Just imagine a day without paper', reads one advertisement for a Finnish paper company. It adds, ‘You almost certainly see our products every day.’. And they're right. But in most industrial countries, people are so (31) _______ to paper - whether it’s for holding their groceries, for drying their hands or for providing them with the daily news - that its (32) _______ in their daily lives passes largely unnoticed. At one (33) _______ paper was in short supply and was used mainly for important documents, but more recently, growing economies and new technologies have (34) _______ a dramatic increase in the amount of paper used. Today, there are more than 450 different grades of paper, all designed for a different purpose. Decades ago, some people predicted a ‘paperless office’. Instead, the widespread use of new technologies has gone hand-in-hand with an increased use of paper. Research into the relationship between paper use and the use of computers has shown that the general (35) _______ is likely to be one of growth and interdependence. However, the costs involved in paper production, in terms of the world's land, water and air resources, are high. This raises some important questions. How much paper do we really need and how much is wasted?  

Question 31:

Choose the word or phrase (A, B, C or D) that best fits the blank space in the following passage:

                                                                                     PAPER

'Just imagine a day without paper', reads one advertisement for a Finnish paper company. It adds, ‘You almost certainly see our products every day.’. And they're right. But in most industrial countries, people are so (31) _______ to paper - whether it’s for holding their groceries, for drying their hands or for providing them with the daily news - that its (32) _______ in their daily lives passes largely unnoticed. At one (33) _______ paper was in short supply and was used mainly for important documents, but more recently, growing economies and new technologies have (34) _______ a dramatic increase in the amount of paper used. Today, there are more than 450 different grades of paper, all designed for a different purpose. Decades ago, some people predicted a ‘paperless office’. Instead, the widespread use of new technologies has gone hand-in-hand with an increased use of paper. Research into the relationship between paper use and the use of computers has shown that the general (35) _______ is likely to be one of growth and interdependence. However, the costs involved in paper production, in terms of the world's land, water and air resources, are high. This raises some important questions. How much paper do we really need and how much is wasted?  

Question 32:

Choose the word or phrase (A, B, C or D) that best fits the blank space in the following passage:

                                                                                     PAPER

'Just imagine a day without paper', reads one advertisement for a Finnish paper company. It adds, ‘You almost certainly see our products every day.’. And they're right. But in most industrial countries, people are so (31) _______ to paper - whether it’s for holding their groceries, for drying their hands or for providing them with the daily news - that its (32) _______ in their daily lives passes largely unnoticed. At one (33) _______ paper was in short supply and was used mainly for important documents, but more recently, growing economies and new technologies have (34) _______ a dramatic increase in the amount of paper used. Today, there are more than 450 different grades of paper, all designed for a different purpose. Decades ago, some people predicted a ‘paperless office’. Instead, the widespread use of new technologies has gone hand-in-hand with an increased use of paper. Research into the relationship between paper use and the use of computers has shown that the general (35) _______ is likely to be one of growth and interdependence. However, the costs involved in paper production, in terms of the world's land, water and air resources, are high. This raises some important questions. How much paper do we really need and how much is wasted?  

Question 33:

Choose the word or phrase (A, B, C or D) that best fits the blank space in the following passage:

                                                                                     PAPER

'Just imagine a day without paper', reads one advertisement for a Finnish paper company. It adds, ‘You almost certainly see our products every day.’. And they're right. But in most industrial countries, people are so (31) _______ to paper - whether it’s for holding their groceries, for drying their hands or for providing them with the daily news - that its (32) _______ in their daily lives passes largely unnoticed. At one (33) _______ paper was in short supply and was used mainly for important documents, but more recently, growing economies and new technologies have (34) _______ a dramatic increase in the amount of paper used. Today, there are more than 450 different grades of paper, all designed for a different purpose. Decades ago, some people predicted a ‘paperless office’. Instead, the widespread use of new technologies has gone hand-in-hand with an increased use of paper. Research into the relationship between paper use and the use of computers has shown that the general (35) _______ is likely to be one of growth and interdependence. However, the costs involved in paper production, in terms of the world's land, water and air resources, are high. This raises some important questions. How much paper do we really need and how much is wasted?  

Question 34: