Muối ăn ở thể rắn là

A. Các phân tử NaCl

B. Các ion Na+ và Cl-

C. Các tinh thể hình lập phương: các ion Na+ và Cl- được phân bố luân phiên đều đặn trên mỗi đỉnh.

D. Các tinh thể hình lập phương: các ion Na+ và Cl- được phân bố luân phiên đều đặn thành từng phân tử riêng rẽ.

Chọn đáp án đúng nhất.

Mục đích của tái bản ADN là

A. chuẩn bị tái tạo lại toàn bộ các bào quan của tế bào.

B. chuẩn bị cho tế bào tổng hợp một lượng lớn prôtêin.

C. chuẩn bị cho tế bào bước vào giai đoạn phân chia tế bào.

D. chuẩn bị tái tạo lại nhân con của tế bào.

Trong điều kiện thích hợp, xảy ra các phản ứng sau:

(1) 2Fe + 6H₂SO₄→ Fe₂(SO₄)₃+ 3SO₂+6H₂O                 (2) 2FeO + 4H₂SO₄→ Fe₂(SO₄)₃+ SO₂+4H₂O

(3) Fe(OH)₂+ H₂SO₄→ FeSO₄+2H₂O                             (4) 2Fe₃O₄+ 10H₂SO₄→ 3Fe₂(SO₄)₃+ SO₂+  10H₂O

Trong các phản ứng trên, phản ứng xảy ra với dung dịch H2SO4  loãng là.

A.(4)                     

B.(3)                     

C.(1)                     

D.(2)

Số đơn vị điện tích hạt nhân của nguyên tử flo là 9. Trong nguyên tử flo, số electron ở mức năng lượng cao nhất là:

A. 2.

B. 5.

C. 9.

D. 11.

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.

Question 46: I would rather you wore something more formal to work.

A. I'd prefer you wearing something more formal to work.

B. I'd prefer you should wear something more formal to work.

C. I'd prefer you to wear something more formal to work.

D. I'd prefer you wear something more formal to work.

làm gì có trang 117 hả bạn

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 36 to 42.

Jupiter is the largest and most massive planet and is fifth in order of distance from the sun. It is well placed for observation for several months in every year and on average is the brightest of the planets apart from Venus, though for relatively brief periods Mars may outshine it. Jupiter's less than 10 hour rotation period gives it the shortest day in the solar system in so far as the principal planets are concerned. There are no true seasons on Jupiter because the axial inclination to the perpendicular of the orbital plane is only just over 3°-less than that for any other planet.

The most famous mark on Jupiter is the Great Red Spot. It has shown variations in both intensity and color, and at times it has been invisible, but it always returns after a few years. At its greatest extent it may be 40,000 kilometers long and 14,000 kilometers wide, so its surface area is greater than that of Earth. Though the latitude of the Red Spot varies little, it drifts about in longitude. Over the past century the total longitudinal drift has amounted to approximately 1200°. The latitude is generally very close to -22°. It was once thought that the Red Spot might be a solid or semisolid body floating in Jupiter's outer gas. However, the Pioneer and Voyager results have refuted that idea and proven the Red Spot to be a phenomenon of Jovian meteorology. Its longevity may well due to its exceptional size, but there are signs that it is decreasing in size, and it may not be permanent. Several smaller red spots have been seen occasionally but have not lasted.

The word "it" in paragraph 2 refers to ______.

A. Jupiter   

B. The Great Red Spot 

C. intensity    

D. color

Cho những nhận xét sau:

(1) Đột biến gen và di-nhập gen đều có thể tạo ra vốn gen phong phú cho quần thể.

(2) Giao phối không ngẫu nhiên là nhân tố tiến hóa có hướng trong việc quy định chiều hướng biến đổi thành phần kiểu gen của quần thể.

(3) Giao phối không ngẫu nhiên và di-nhập gen đều có thể làm nghèo vốn gen của quần thể.

(4) Chọn lọc tự nhiên và yếu tố ngẫu nhiên đều làm giảm sự đa dạng di truyền của quần thể.

(5) Giao phối ngẫu nhiên và đột biến gen đều là nhân tố tiến hóa vô hướng.

(6) Đột biến và giao phối không ngẫu nhiên đều làm thay đổi tần số alen của quần thể một cách chậm chạp.

(7) Chọn lọc tự nhiên và yếu tố ngẫu nhiên làm thay đổi tần số alen một cách đột ngột.

(8) Đột biến thay đổi tần số alen chậm nhất, chọn lọc tự nhiên làm thay đổi tần số alen nhanh nhất.

Có bao nhiêu nhận xét sai?

A. 4

B. 5

C. 2

D. 3.

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

David Beckham is an English footballer who has played for Manchester United and Real Madrid, as well as representing his country 100 times. He moved to the Los Angeles Galaxy in 2007 to increase the profile of football in America. He married Spice Girl Victoria Beckham and has become a worldwide celebrity, an advertising brand and a fashion icon. Beckham was born in London in 1975. His parents were fanatical Manchester United supporters. His talent was obvious from an early age and he signed with Manchester United on his fourteenth birthday. He helped the youth team win several trophies and made his first team debut in 1995. He helped his team achieve considerable success in his eleven seasons with them.

Beckham has been runner-up twice as world football's best player. He won many trophies  with Manchester United, including the Champions League, and won a league title with Real Madrid. He also captained his club and country. He was famously sent off in a match against Argentina in the 1998 World Cup. In 2003, Beckham received an honour for services to football from Britain's Queen.

Beckham has many interests off the soccer pitch and is rarely out of the headlines, especially concerning his marriage and children. He has established football academies in Los Angeles and London. In 2006 he was named a judge for the British Book Awards. He lives near Tom Cruise and the two are best buddies. Beckham is also a United Nations Goodwill Ambassador.

(Source: haps://www.famouspeoplelessons.corn)

According to the passage, Beckham has played 100 times for ______.

A. Real Madrid

B. Manchester United 

C. the national team of America

D. The national team of England

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.

In the 1960s, The Beatles were probably the most famous pop group in the whole world. Since then, there have been a great many groups that have achieved enormous fame, so it is perhaps difficult now to imagine how sensational The Beatles were at that time. They were four boys from the north of England and none of them had any training in music. They started by performing and recording songs by black Americans and they had some success with these songs. Then they started writing their own songs and that was when they became really popular. The Beatles changed pop music. They were the first pop group to achieve great success from songs they had written themselves. After that it became common for groups and singers to write their own songs. The Beatles did not have a long career. Their first hit record was in 1963 and they split up in 1970. They stopped doing live performances in 1966 because it had become too dangerous for them – their fans were so excited that they surrounded them and tried to take their clothes as souvenirs! However, today some of their songs remain as famous as they were when they first came out. Throughout the world many people can sing part of a Beatles song if you ask them.

The four boys of the Beatles___________

A. Were at the same age

B. Came from a town in the north of England

C. Came from the same family

D. Received good training in music