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dominhhoang20
2 năm trước
cho tam giác ABC vuông tại A có góc A=30 độ, BC=a gọi I là trung điểm của AC. Hãy tính độ dài vectơ [AB+AC]
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Bài 13: Khoanh vào đáp án đúng. Elephants need help The elephant is (1) _______ unique cultural symbol of Tay Nguyen and Dak lak is considered the land of (2) ________ elephants in Vietnam. In the past.Tay Nguyen used to have large (3) __________ of elephants living in the mountains. They helped (4) ______locals and they lived in harmony with people. However, the elephants in Tay Nguyen are in (5) _____ now. In recent years, climate changes have decreased the area of natural forests. Illegal deforestation has also threaten the elephants. Besides, illegal hunting for tusks, bones and tail hair has killed many of (6) __________ animals, (7) ________can we protect the elephants? It is important that both the authorities and the local people joined hands to save the elephants from (8) ______. 1. A. a B. an C. the D. 0 2. A. a B. an C. the D. 0 3. A. shoals B. schools C. herds D. flocks 4. A. a B. an C. the D. 0 5. A. safe B. guard C. danger D. protection 6. A. a B. an C. the D. 0 7. A. How B. What C. Who D. Why 8. A. extinction B. protection C. destruction D. conservation Bài 14: Đọc bài đọc dưới đây và trả lời câu hỏi. NGOC LU BRONZE DRUM Dong Son bronze drums are very famous for its cultural value. They are often used as a musical instrument in festivals and rituals. Of about 200 drums discovered, Ngoc Lu bronze drum is considered the most beautiful drum of the Dong Son culture ever found in Vietnam. It is now preserved at the National Museum of Vietnam History in Hanoi. This drum has a large size and an ancient look with many decorative patterns. These patterns include a multi-ray star (symbolizing the shining sun) and in between the star rays are designs of stylized peacock feathers. Bands of geometrical patterns with small dots surround the star. The band of human figures presents two people pounding rice, some other standing or sitting inside the house, some beating the drum and many others dancing. In between those human patterns are the curved-roof stilted house, bronze drum, bronze bells, weapons, musical instruments and so on. The bands of animal figures include short –bill birds, the long –bill birds and deer. The Ngoc Lu bronze drum is the most typical one in the bronze drum system of Vietnam, and at the same time it symbolizes the brilliant peak of the Dong Son culture. The drum represents the scientific knowledge and the artistic talent and mind of the ancient Viet. 1. What are Dong Son bronze drums famous for? ……………………………………………………………………………… 2. Which bronze drum is considered the most beautiful drum of the Dong Son culture? ………………………………………………………………………………. 3. Where is the Ngoc Lu bronze drum preserved now? ……………………………………………………………………………….. 4. What decorative patterns are in between the star rays? ………………………………………………………………………………. 5. What does the band of animal figures include? ………………………………………………………………………………. 6. What does the Ngoc Lu bronze drum symbolize? ………………………………………………………………………………..

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