P có kiểu gen  x. Nếu xảy ra  trao đổi chéo ở cả 2 giới thì số kiểu gen ở F1 là:  

Cho tập hợp có phần tử. Tìm số tập con gồm phần tử của .         

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________.               

Cho đa giác đều có đỉnh. Số tam giác được tạo nên từ các đỉnh này là:        

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?         

Cho số tự nhiên thỏa mãn . Mệnh đề nào sau đây là đúng?         

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_________.         

Một lớp có học sinh. Hỏi có bao nhiêu cách chọn ra người làm cán sự lớp ?

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: What did the five campers do when they saw a group of apelike creatures?         

Trong các đẳng thức sau,đẳng thức nào sai?

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 called the apelike creatures 'Sasquatch'?