Ban đầu có một mẫu  P 210 o  nguyên chất, sau một thời gian nó phóng xạ  α  và chuyển thành hạt nhân chì  P 206 b bền với chu kì bán rã 138,38 ngày. Hỏi sau bao lâu thì tỉ lệ giữa khối lượng chì và khối lượng Poloni còn lại trong mẫu là 0,7? 

A. 108,8 ngày 

B. 106,8 ngày 

C. 109,2 ngày 

D. 107,5 ngày 

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.

A scientist said robots will be more intelligent than humans by 2029. The scientist's name is Ray Kurzweil. He works for Google as Director of Engineering. He is one of the world‘s leading experts on (25)______  intelligence (A.l). Mr Kurzweil believes computers will be able to learn from experiences, just like humans. He also thinks they will be able to tell jokes and stories, and even flirt. Kurzweil‘s 2029 prediction is a lot sooner than many people thought. The scientist said that in 1999, many A.I. experts said it would be hundreds of years (26)____ a computer was more intelligent than a human. He said that it would not be long before computer (27)______ is one billion times more powerful than the human brain.

 Mr Kurzweil joked that many years ago, people thought he was a little crazy for predicting computers would be as intelligent as humans. His thinking has stayed the same but everyone else has changed the way they think. He said: “My views are not radical any more. I've actually stayed (28)______. It's the rest of the world that's changing its View.” He highlighted examples of high-tech things we use, see or read about every day. These things make us believe that computers have intelligence. He said people think differently now: "Because the public has seen things like Siri (the iPhone’s voice-recognition technology) (29)______ you talk to a computer, they've seen the Google self-driving cars."

(Source: https://breakingnewsenglish.com)

Điền vào số 26

A. while

B. after 

C. then 

D. before

Khai thác rừng hiện nay ở Việt Nam phải tuân theo các điều kiện nào?

* Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Your sister has lost an awful lot of weight. She must have been on a diet,_________?

A. mustn’t she

B. needn’t she

C. haven’t she

D. hasn’t she

Ở ruồi giấm, một học sinh quan sát quá trình giảm phân hình thành giao tử của 1 tế bào sinh dục có kiểu gen   A a B b D e d E từ đó ghi vào sổ thí nghiệm 1 số nhận xét sau đây:

(1). Tùy thuộc các xếp hàng của NST trong kỳ giữa I mà quá trình có thể tạo ra 16 loại giao tử khác nhau.

(2). Hiện tượng hoán vị xảy ra đối với cặp NST D e d E và tạo ra 4 loại giao tử riêng biệt liên quan đến cặp NST này.

(3) Nếu tạo ra loại giao tử ABDeY thì nó sẽ chiếm tỷ lệ 1/2 trong tổng số giao tử tạo ra.

(4) Tính trạng do gen H chi phối chỉ xuất hiện ở giới đực mà không xuất hiện ở giới cái. Số nhận xét chính xác là:

A. 1

B. 2

C. 3

D. 4

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 33 to 37. 
        CARE was (33) _____ in 1945 to help people after World War II. It distributed over 100 million food (34) _____. Meanwhile, it was starting self-help programs. Today it has development programs in 37 countries. CARE gives equipment and (35) _____ people how to build water systems, roads, schools and health centers. It also teaches people how to increase production on farms, how to reforest areas, and how to (36) _____ small village industries. Doctors and nurses volunteer to go to villages. They provide health care for the people. They also teach people how to improve their health. They train people to provide (37) _____ medical care. CARE also provides food for about 30 million people every year. Most of them are children. It gives special help where there is a flood, an earthquake, a drought or a war.

(Điền vào số 36)

A. start       

B. begin      

C. take up   

D. turn on