Trong tọa độ mặt phẳng Oxy hãy biểu diễn tọa độ của các BPT sau x-2y<2 3x-2y ≥0 0x+2y ≤6

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Choose the sentences that have the same meaning as the given ones. 6. I wasn't hungry, so I didn't eat anything. A. If I'd been hungry, I would have eaten something. B. If I had been hungry, I would eat something. C. If I was hungry, I would eat something. D. If I wasn’t hungry, I would eat something. 7. The accident happened because the road was icy. A. If the road had been icy, the accident would happen. B. If the road had icy, the accident would have happened. C. If the road had been icy, the accident would have happened. D. If the road had icy, the accident would happened. 8. I didn't know that Joe had to get up early, so I didn't wake him up. A. If I know that Joe had to get up early, I will wake him up. B. If I knew that Joe had to get up early, I would wake him up. C. If I had knew that Joe had to get up early, I would have woken him up. D. If I had known that Joe had to get up early, I would have woken him up. 9. I was able to buy the car only because Jane lent me the money. A. If I had had a lot of money, I would have bought the car. B. If Jane had lent me the money, I would buy the car. C. If I buy the car, Jane will lend me the money. D. If I lend Jane the money, I was able to buy the car. 10. Karen wasn't injured in the crash because she was wearing a seat belt. A. If Karen wears a seat belt, she will not injure in the crash. B. If Karen had worn a seat belt, she would injure in the crash. C. If Karen hadn’t worn a seat belt, she wouldn’t have injured in the crash. D. If Karen wore a seat belt, she would injure in the crash.

Read the text about the jungle town. Choose the best answer A, B, C or D The jungle town lost to tourists The small Amazonian town of Nazareth, just 20 minutes by boat from the city, is a traveller’s dream. But tourists might have to give the place a miss in future as residents have chosen to refuse entry to travellers. Nazareth residents say that most of the tourists’ money goes to travel agencies, not locals. They believe some tourists can’t see the difference between the wildlife and residents, taking photos of local families as if they were just another kind of animal. And what a tourist may think are polite questions about the local culture, often make them seem rude to local people. The actions taken by the Nazareth townspeople have uncovered a difference of opinion among residents in local Amazon towns about what role tourism should play in the region’s development. With the rise of eco-tourism, the place has seen more travellers arrive to swim with the dolphins, hike through the rainforests and admire the water as the sun rises. An amazing 35,000 people travelled to the region last year. But as Nazareth residents complain, the local people have so far seen few of the benefits and mostly just the disadvantages. Residents in other towns, however, believe that well-controlled tourism can help improve living conditions in the area. 1.What is the writer trying to do in this text? A.Warn people against travelling to the Amazon. B.Report the decision of a village in the Amazon. C.Describe the negative effects of tourism in the Amazon. D.Explain why the Amazon is a dream destination. 2.Nazareth residents believe that visitors __________. A.aren’t interested in seeing how they live. B.take more photos of animals than people. C.enjoy photographing the local wildlife. D.deal with people and animals in the same way. 3.What does the situation in Nazareth say about people in other towns nearby? A.They agree about the effects of tourism. B.They have planned for their development. C.They take different views on tourism. D.They think the role of tourism is important. 4.What do we learn about the increase in tourism? A.It has not benefited everyone. B.It will have a negative effect on wildlife. C.It was not predicted by local people. D.It has been welcomed by everyone. 5.What might a tourist say about a visit to Nazareth? A.It's a long boat ride from the nearest city but it's worth it. B.The local people refused to let us ask them questions. C.The residents were given money by our travel agent. D.Travellers aren't allowed to swim with the local sea life.

6 Oxi lỏng có màu * Đỏ Xanh nhạt Cam Hồng 7 Đốt cháy 6,4 gam đồng trong 5,6 lít khí oxi (ở đktc). Sau phản ứng thấy có m gam chất rắn tạo ra. Giá trị m là * 4 gam 8 gam 10 gam 0,8 gam 8 Chọn phát biểu chưa đúng * Oxi tạo oxit bazơ với hầu hết các kim loại Oxi là chất khí không màu, mùi hắc Oxi duy trì sự sống và duy trì sự cháy Oxi oxi hóa các chất dinh dưỡng trong cơ thể để giải phóng năng lượng. 9 Đốt cháy 2,4 gam Mg trong bình chứa 8 gam oxi. Sau phản ứng chất nào phản ứng hết. * Oxi Magie Hai chất vừa hết Không xác định được 10 Đốt cháy 3,2 gam lưu huỳnh (S) trong 1,12 lít khí oxi (O2) ở đktc. Sau phản ứng ta chứng minh được * Dư oxi Dư lưu huỳnh Hai chất phản ứng hết Cả hai chất còn dư 11 Sự oxi hóa chậm là * Sự oxi hóa có tỏa nhiệt và phát sáng. Sự oxi hóa có tỏa nhiệt nhưng không phát sáng. Sự oxi hóa không tỏa nhiệt nhưng có phát sáng. Sự oxi hóa không tỏa nhiệt và không phát sáng. 12 Để oxi hóa hoàn toàn một kim loại M hóa trị II thành oxit phải dùng một lượng oxi bằng 25% lượng kim loại đã dùng. Kim loại M là * Cu Ca Zn Ba 13 Phản ứng hóa hợp là: a) 2KClO3 → 2KCl + 3O2. b) 2Fe(OH)3 → Fe2O3 + H2O. c) 2Fe + 3Cl2 → 2FeCl3. d) H2O + CaO → Ca(OH)2 * a, b. b, d. a, c. c, d. 14 Oxi hóa lỏng ở nhiệt độ: * 183 độ C - 183 độ C 196 độ C - 196 độ C 15 Khối lượng (gam) và thể tích (lít) khí oxi đủ dùng để đốt cháy hoàn toàn 3,1 gam photpho lần lượt là * 5,6 và 8. 8 và 5,6. 4 và 2,8. 2,8 và 4. 16 Trong bể nuôi cá cảnh, người ta lắp thêm máy sục khí là để * Làm đẹp Cung cấp nitơ cho cá Cung cấp oxi cho cá Cung cấp thêm khí cacbonic cho cá 17 Chọn câu trả lời đúng trong các câu sau đây về thành phần theo thể tích của không khí * 21% khí nitơ ; 78% khí oxi ; 1% các khí khác (CO2, CO, khí hiếm). 21% các khí khác (CO2, CO, khí hiếm) ; 78% khí nitơ ; 1% khí oxi. 21% khí oxi ; 78% khí nitơ ; 1% các khí khác (CO2, CO, khí hiếm). 21% khí oxi ; 78% các khí khác (CO2, CO, khí hiếm) ; 1% khí nitơ. 18 Lưu huỳnh cháy trong không khí là do * Lưu huỳnh tác dụng với khí cacbon đioxit Lưu huỳnh tác dụng với oxi và nitơ Lưu huỳnh tác dụng với nitơ Lưu huỳnh tác dụng với oxi 19 Không khí là: (chọn khẳng định đúng) * Một chất Một đơn chất Một hỗn hợp Mộ hợp chất 20 Đốt cháy hết 1,6 gam CH4 thu được 4,4 gam CO2 và 3,6 gam H2O. Khối lượng O2 cần để đốt là * 3,2 gam 6,4 gam 4,6 gam 2,3 gam