1. Cho tam giác ABC vuông tại A.Gọi M là trung điểm của BC. Trên tia đối của tia MA lấy điểm E sao cho ME=MA A) Tính số đo của góc ABC khi ACB=40 B) Chứng minh tam giác AMB=tam giác EMC và AB//EC C) Từ C kẻ đường thẳng (d) song song với AE. Kẻ EK vuông góc với đường thẳng (d) tại K. cHỨNG minh góc KEC=BCA

Bằng phương pháp hóa học hãy phân biệt giữa ∆ Anken & Ankin ∆ Ankan & Ankin Giúp mình với. Cảm ơn nhìu

mọi người giúp mình nhé mình cảm ơn

Tích vào đáp án đúng giúp mình với. Cảm ơn nhé

Nêu đặc điểm giai đoạn thứ ba : giai đoạn tân kiến tạo

Lớp 5A có 40 học sinh trong đó học sinh nam là 24 em hỏi tỉ số phần trăm của học sinh nam và và cả lớp là bao nhiêu?

Cho tam giác ABC vương tại A bới AB/AC = 3/4 và BC =15cm. Tia phân giác của góc C cắt AB tại D. Kẻ DE vuông góc với BC (E thuộc BC) a) CM:AC=CE b) Rính độ dài AB, AC c) Trên tia AB lấy điểm F sao cho AF=AC. KẺ Fx vuông góc FA cắt tia DE tại M. Tính góc DCM

tìm số nguyên n sao cho -13 là bội của 2n-1

I>Fill in each blank with one suitable relative pronoun (who, whom, whose, which) or relative adverb (where, when). 1. The man ____________ your mother is talking to is my English teacher. 2. Ha Long Bay is a beautiful spot ____________ thousands of tourists visit every year. 3. The students ____________are standing in front of the library is my classmates. 4. Hoa’s parents ____________ are farmers work very hard to earn their living. 5. The children like to play football ____________ is very popular in our country. 6. These are the latest news ____________ you might want to know. 7. Ba and his friends are fond of the performing animals ____________ have just come to town. 8. The beach ____________ the students are cleaning up the trash is a beautiful one. 9. The parrot ____________ can speak some words belongs to my close friend. 10. This is the best movie ____________ I have seen. 11. He is enjoys reading books ____________ are on computer science. 12. Mother’s Day is the day ____________. the children show their love to their mother. 13. Tet is a Vietnamese festival ____________ takes place in late January or early February. 14. The little girl ____________ is wearing the red dress sings beautifully. 15. Thu enjoyed her trip to Da Lat ____________ her grandparents lived long ago. 16. Lan’s parents came back to Ha Noi ____________ they visited last year. 17. They like Asian food ____________ is sold in that market. 18. Mary, ____________ sits next to me, is good at maths. 19. My office, ____________ is on the second floor of the building, is not very big. 20. That’s Jack, ____________ lives next door. II.Join the sentences. Use relative pronouns: who, which , whose : 1. I have a class. It begins at 8.00a.m. ……………………………………………………………………………. 2. I don’t know the man. He is talking to Rita. ……………………………………………………………………………… 3. I know the man. His bicycle was stolen. ……………………………………………………………………………... 4. On my mom’s birthday my Dad gave her roses. The roses were very sweet and beautiful. …………………………………………………………………………… I am using a sentence. It contains an adjective clause. ……………………………………………………………………………. 5. I don’t know the woman. She is standing over there. …………………………………………………………………………… 6. I know the man. His son died in the war …………………………………………………………………………... 8. I like reading books. Books tell about different people and their cultures. …………………………………………………………………………… 9. Tomorrow I’ll go to the airport to meet my friends. My friends come to stay with us during the Christmas. ……………………………………………………………………………… 10. We often go to the town culture house. The town culture house always opens on public holidays. ………………………………………………………………………………………

lấy 2 VD về a,sự cháy b,sự oxi hoá chậm