Đốt cháy hoàn toàn 3,78 gam hợp chất hữu cơ X chỉ thu được 11,88 gam CO2 và 4,86 gam H2O . X tác dụng với HBr chỉ thu được 1 sản phẩm Y duy nhất , trong Y có chứa 43,64 cacbon về khối lượng . Số công thức cấu tạo của X thỏa mãn điều kiện trên là: A.2. B.1. C.3. D.4

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B.Vocabulary and grammar I.Choose the best answer. 1.What ………………yesterday evening? a.have done b.do you do c. did you do d.are you doing 2………….can help us watch TV programmes from space. a.Robots b.Wireless TVs c.Remote controls d.Automatic dishwashers 3.This picture looks very nice,……………..? a.is it b.does it c.doesn’t it d.isn’t it 4.The future robots will be able to………….our house when we are far from. a.guard b.look after c.keep d.a,b or c II.Write conditional sentences type 1. 1.If the river (not be)……………….dirty, there (be)…………..more fish for us. 2.If people (be)…….active in work and free time, they (probably be )………………healthier. 3.If Nam (do)………………..a lot of exercises, he (stay) ……………..fit and healthy. 4.If I (go )………. to Ha Long this summer, I (take ) …………….a lot of beautiful photos there III.Supply the correct form of the word. 1.These plastic bottles are (use)…………………Don’t throw them away. 2.My sister is (create)………………She paints a lot. C.Reading. I.Read the passage and choose the best option. I’m in New York.I’ve been here a day now. It’s a really (1)……………place! I’ve been very busy and I have done a lot of exciting things. I’ve visited the Statue of Liberty and I’ve (2)……….lots of photos. I haven’t been (3)………………..a boat trip yet. I am going to do that tomorrow. I’ve been to the (4)………. and I’ve bought some souvenirs. 1.a.surprised b.amazing c.interested d.bored 2.a.taken b. takes c.taking d.take 3.a.in b.under c.with d.on 4.a.shopping b.shops c.to shop d.shopps II.Read the text and decide whether each statement below is true (T) or false (F) If we don’t recycle plastic and glass, they stay in the ground for a long time. Dangerous chemicals can also go underground, where they are harmful to plants and animals. whenever we recycle bottles and cans ,we reduce land pollution. 1.Plastic , glass and chemicals underground are harmful to plants and animals. 2.We should recycle plastic and glass to reduce land pollution. D.Writing -I.Write the sentences using the cues below. 1.These robots /in 10years.//will be able to /old people /take care of / =>………………………………………………………………………………………… 2.we /much money ./ if we use / will save /many recycled things / =>……………………………………………………………………………………… II. Combine each pair of sentences below to make a conditional sentence type 1. 1.You don’t finish your homework. You get the bad marks. => If …………………………………………………………………………………… 2. She works hard all the time. She passes the exams. =>If …………………………………………………………………………………… Bạn nào làm nhanh và đúng mình sẽ vote 5 sao và 5 câu trả lời hay nhất