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

Scientists do not yet thoroughly understand just how the body of an individual becomes sensitive to a substance that is harmless or even wholesome for the average person. Milk, wheat, and egg, for example, rank among the most healthful and widely used foods. Yet these foods can cause persons sensitive to them to suffer greatly. At first, the body of the individual is not harmed by coming into contact with the substance. After a varying interval of time, usually longer than a few weeks, the body becomes sensitive to it, and an allergy has begun to develop. Sometimes it's hard to figure out if you have a food allergy, since it can show up so many different ways. Your symptoms could be caused by many other problems. You may have rashes, hives, joint pains mimicking arthritis, headaches, irritability, or depression. The most common food allergies are to milk, eggs, seafood, wheat, nuts, seeds, chocolate, oranges, and tomatoes. Many of these allergies will not develop if these foods are not fed to an infant until her or his intestines mature at around seven months. Breast milk also tends to be protective. Migraines can be set off by foods containing tyramine, phenathylamine, monosodium glutamate, or sodium nitrate. Common foods which contain these are chocolate, aged cheeses, sour cream, red wine, pickled herring, chicken livers, avocados, ripe bananas, cured meats, many Oriental and prepared foods (read the labels!). Some people have been successful in treating their migraines with supplements of B-vitamins, particularly B6 and niacin. Children who are hyperactive may benefit from eliminating food additives, especially colorings, and foods high in salicylates from their diets.

The topic of this passage is______________.

A. reactions to foods

B. food and nutrition 

C. infants and allergies 

D. a good diet

xấu thế!

- Giữa năm 1786, Nguyễn Huệ tiến quân ra Bắc, diệt họ Trịnh.
- Trở về Nam, Nguyễn Hữu Chỉnh mưu phản, Nguyễn Huệ cử Vũ Văn Nhậm ra Bắc diệt Chỉnh..
- Giữa năm 1788, Nguyễn Huệ tiến quân ra Bắc diệt Nhậm. Lê Chiêu Thống chạy sang Kinh Bắc (Bắc Ninh, Bắc Giang)...

4/

-Cuộc khởi nghĩa mang tính chất quyết liệt của phong trào nông dân chống lại chế độ phong kiến bất công đương thời.

-Cuộc khởi nghĩa có quy mô rộng khắp cả Đàng Ngoài, từ đồng bằng đến miền núi.

2/

Điểm nổi bật ở các thế kỉ này là sự phục hồi và phát triển của nghệ thuật dân gian. Nhiều khách nước ngoài đến nước ta thế kỉ XVII còn được xem biểu diễn múa trên dây, múa đèn và các trò ảo thuật. Điêu khắc gỗ trong các đình, chùa diễn tả cảnh sinh hoạt thường ngày ở nông thôn (chèo thuyền, đấu vật, chọi gà, đi cày, tắm ao, đánh cờ...), nét chạm trổ đơn giản mà dứt khoát.
Nghệ thuật sân khấu cũng đa dạng và phong phú. Khắp nông thôn, đâu đâu cũng có gánh hát. Nội dung các vở chèo, tuồng, hát ả đào... thường phản ánh đời sống lao động cần cù, vất vả nhưng lạc quan của nhân dân, lên án kẻ gian nịnh và ca ngợi tình thương yêu con người.
Khách nước ngoài đã ghi lại bằng những kí hoạ cảnh biểu diễn múa trên dây, đánh đu, luyện võ... ở nước ta thời bấy giờ.

1 công nhân làm trong :

15 x 6 = 90 (ngày)

Làm trong 3 ngày thì cần :

90 : 3 = 30 (người)

Vậy cần bổ sung thêm:

30 - 15 = 15 (người)

Đáp số:15 người

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 38 to 42.

(1) Though Edmund Halley was most famous because of his achievements as an astronomer, he was a scientist of diverse interests and great skill. In addition to studying the skies, Halley was also deeply interested in exploring the unknown depths of the oceans. One of his lesser-known accomplishments that were quite remarkable was his design for a diving bell that facilitated exploration of the watery depths.

(2) The diving bell that Halley designed had a major advantage over the diving bells that were in use prior to his. Earlier diving bells could only make use of the air contained within the bell itself, so divers had to surface when the air inside the bell ran low. Halley’s bell was an improvement in that its design allowed for an additional supply of fresh air that enabled a crew of divers to remain underwater for several hours.

(3) The diving contraption that Halley designed was in the shape of a bell that measured three feet across the top and five feet across the bottom and could hold several divers comfortably; it was open at the bottom so that divers could swim in and out at will. The bell was built of wood, which was first heavily tarred to make it water repellent and was then covered with a half-ton sheet of lead to make the bell heavy enough to sink in water. The bell shape held air inside for the divers to breathe as the bell sank to the bottom.

(4) The air inside the bell was not the only source of air for the divers to breathe, and it was this improvement that made Halley’s bell superior to its predecessors. In addition to the air already in the bell, air was also supplied to the divers from a lead barrel that was lowered to the ocean floor close to the bell itself. Air flowed through a leather pipe from the lead barrel on the ocean floor to the bell. The diver could breathe the air from a position inside the bell, or he could move around outside the bell wearing a diving suit that consisted of a lead bell-shaped helmet with a glass viewing window and a leather body suit, with a leather pipe carrying fresh air from the diving bell to the helmet. 

It is NOT stated in the passage that Halley’s bell _____.

A. was completely enclosed

B. was wider at the top than at the bottom 

C. could hold more than one diver

D. was made of tarred wood