Cho biết mỗi cặp gen quy định một cặp tính trạng, alen trội là trội hoàn toàn, hoán vị gen xảy ra ở cả 2 giới với tần số 40%. Tiến hành phép lai ♂ A B a b D d  × ♀ A b a B D d , thu được F₁. Lấy ngẫu nhiên 2 cá thể F₁, xác suất để trong đó có 1 cá thể có kiểu hình mang hai tính trạng trội và một tính trạng lặn là:

A. 17,275%

B. 39,875%.

C. 48,875%

D. 52,275%.

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

   In the exploration of the linguistic life cycle, it is apparent that it is much more difficult to learn a second language in adulthood than a first language in childhood. Most adults never completely master foreign language, especially in phonology - hence the ubiquitous foreign accent. Their development often "fossilizes" into permanent error patterns that no teaching or correction can do. Of course, there are great individual differences, which depend on effort, attitudes, amount of exposure, quality of teaching and plain talent, but there seems to be a cap for the best adults in the best circumstances.

   Many explanations have been advanced for children's superiority: they exploit Motherless (the simplified, repetitive conversation between parents and children), make errors oneself- consciously, are more motivated to communicate, like to conform, are not set in their ways, and have no first language to interfere. But some of these accounts are unlikely, based on what is known about how language acquisition works. Recent evidence is calling these social and motivation explanations into doubt. Holding every other factor constant, a key factor stands out: sheer age.

   Systematic evidence comes from the psychologist Elisa Newport and her colleagues. They tested Korean and Chinese-born students at the University of Illinois who had spent at least ten years in the United States. The immigrants were given a list of 276 simple English sentences, half of them containing some grammatical errors. The immigrants who came to the United States between the ages of 3 and 7 performed identically to American bom students. Those who arrived between the ages of 8 and 15 did worse the later they arrived, and those who arrived between 17 and 39 did the worst of all, and showed huge variability unrelated to their age of arrival.

What does the word "Those'' in the last paragraph refer to?

A. Korean and Chinese-born students

B. American-born students

C. different age groups

D. English sentences

Ở một loài thực vật, trên nhiễm sắc thể số 1 có trình tự các  gen như sau : ABCDEGHIK. Do đột biến nên trình tự các gen trên nhiễm sắc thể này là ABHGEDCIK. Đột biến này thuộc dạng

A. đảo đoạn nhiễm sắc thể

B. mất đoạn nhiễm sắc thể

C. chuyển đoạn giữa hai nhiễm sắc thể

D. lặp đoạn nhiễm sắc thể

Phân supe phốtphat kép thành phần chứa

A. Ca(H₂PO₄)₂ + CaSO₄

B. Ca₃(PO₄)_{2 +} CaF₂

C. CaHPO₄

D. Ca(H₂PO₄)₂

Read the following passage on transport, 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.

No educational medium better as means of spatial communication than the atlas. Atlases deal with such invaluable information as population distribution and density. One of the best, Pennycooke's World Atlas, has been widely accepted as a standard owing to the quality of its maps and photographs, which not only show various settlements but also portray them in a variety of scales. In fact, the very first map in the atlas is a cleverly designed population cartogram that projects the size of each country if geographical size were proportional to population. Following the proportional layout, a sequence of smaller maps shows the world’s population density, each country’s birth and death rates, population increase or decrease, industrialization, urbanization, gross national product in terms of per capita income, the quality of medical care, literacy, and language. To give readers a perspective on how their own country fits in with the global view, additional projections depict the world's patterns in nutrition, calorie and protein consumption, health care, number of physicians per unit of population, and life expectancy by region. Population density maps on a subcontinental scale, as well as political maps. Convey the diverse demographic phenomena of the world in a broad array of scales.

The author of the passage implies that _____.

A. atlases provide a bird's eye view of countries   

B. maps use a variety of scales in each projection

C. maps of countries differ in size     

D. atlases can be versatile instrument

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 25 to 29.

VIRTUAL DOCTORS

Clare Harrison rarely falls ill and hates going to the doctor’s when she does. So when she recently (25) _________ out in a painful rash down one side of her body she emailed her symptoms, (26) _______ also included a (27) _________ fever, to e-doc, the internet medical service. Two hours later she was diagnosed as having shingles (Herpes Zoster) by her online doctor, who prescribed a special cleansing solution for the rash and analgesics to help relieve the pain.

Health advice is now the second most popular topic that people search for on the internet, and online medical consultation is big business. Sites vary enormously in what they offer, with services ranging from the equivalent of a medical agony aunt to a live chat with a doctor via email. They are clearly (28) _________ a demand from people who are too busy or, in some cases, too embarrassed to discuss their medical (29) _________ with their GP.

Điền vào ô trống 28

A. serving 

B. meeting 

C. creating 

D. establishing 

Trong một đêm khuya, để chuẩn bị cho chiến dịch ngày mai, Bác Hồ ở cùng lán với bộ đội trong rừng. Bên bếp lửa, Bác không ngủ vì thương đoàn dân công giờ này còn phải chịu rét mướt khổ sở ngoài rừng sâu mưa đêm rả rích. Bác không ngủ nên Bác đi lại săn sóc giấc ngủ cho những người bộ độ để sáng hôm sau hành quân đi vào các trận đánh với quân thù.

Phản ứng CH₃COOH + CH º CH ® CH₃COOCH = CH₂ thuộc loại phản ứng nào sau đây?

A. Phản ứng thế

B. Phản ứng cộng

C. Phản ứng tách

D. Không thuộc về ba loại phản ứng trên