Bài 18. Cho tam giác ABC có góc A = 90 độ. Qua B kẻ tia BM // AC (tia BM thuộc nửa mặt phẳng bờ là đường thẳng AB có chứa điểm C) a) Chứng minh BM vuông góc AB b) Trên cùng một nửa mặt phẳng bờ BC có chứa điểm A, vẽ về phía ngoài \Delta ABC hai tia Bx và tia Cy sao cho góc xBA=góc yCA= 45 độ. Chứng tỏ Bx // Cy c) Vẽ tia BN sao cho Bx là tia phân giác của NBA. Chứng minh 3 điểm B, M, N thẳng hàng. bạn nào lm giúp mik bài này với

Cho nước vào cốc có chứa 80 ml rượu etylic cho đến vạch 200ml thì rượu thu được có độ rượu là

mọi người giúp mik bài này vs nhá

Tam giác ABC vuông tại A có AB=AC=a .Điểm M nằm trên BC sao cho BM=BC/3.Độ dài AM bằng bao nhiêu.giúp mình vs

Giúp với mọi người tôi sẽ cho 5 ☆

mọi người giúp em giải với ạ nếu ai trả lời xong trước ngày 22/3/2020 mà đúng thì em sẽ vote 5 sao cảm ơn 5: Rewrite these sentences using participle or infinitive phrases. 1. The doctor who examined the sick child was very gentle. _______________________________________________________________________ 2. The house is being built now belongs to Mr. Pike. _______________________________________________________________________ 3. The students who were punished by the teacher are lazy. _______________________________________________________________________ 4. A river which is polluted is not safe for swimming. _______________________________________________________________________ 5. Yuri Gagarin was the first man who flew into space. _______________________________________________________________________ 6. The man who keeps the school library is Mr. Green. _______________________________________________________________________ 7. Do you know the boy who broke the windows last night? _______________________________________________________________________ 8. The envelope which lies on the table has no stamp on it. _______________________________________________________________________ 9. I haven’t anyone that can go with. _______________________________________________________________________ 10. I know the man who painted this picture. _______________________________________________________________________ 11. The last person who leaves the room must turn off the light. _______________________________________________________________________ 12. They live in a house that was built in 1980. _______________________________________________________________________ 13. The first person who catches the ball will be the winner. _______________________________________________________________________ 14. I come from a city that is located in the southern part of the country. _______________________________________________________________________ 15. We have an apartment which overlooks the park. _______________________________________________________________________ 16. The fence which surrounds our house is made of wood. _______________________________________________________________________ 17. The ideas which are presented in that book are interesting. _______________________________________________________________________ 18. This is the second person who was killed in that way. _______________________________________________________________________ 19. They work in a hospital which was sponsored by the government. _______________________________________________________________________ 20. The boy who is playing the piano is Ben. _______________________________________________________________________ 21. The Queen Elizabeth is the largest ship which has been built on the Clyde. _______________________________________________________________________ 22. here are some account that you must check. _______________________________________________________________________ 23. My brother is the only one who realize the danger. _______________________________________________________________________ 24. We had a river in which we could swim. _______________________________________________________________________ 25. She said that she wasn’t going to buy any cards; she hadn’t anyone to whom she could send cards. _______________________________________________________________________ 26. Neil Armstrong was the first man who walked on the moon. _______________________________________________________________________ 27. The fifth man who was interviewed was entirely unsuitable. _______________________________________________________________________ 28. I wish we had a garden that my children could play in. _______________________________________________________________________ 29. I have some homework that I must do today. _______________________________________________________________________ 30. Have you bought a book that Kevin can read . _______________________________________________________________________ 31. The couples who live in the house next door are both college professors. _______________________________________________________________________ 32. A knuckle is a point that connects a finger to the rest of the hand. _______________________________________________________________________ 33. Our solar system is in a galaxy that is called the Milky Way. _______________________________________________________________________ 34. The children attended a special movie program that consisted of cartoons that featured Donald Duck and Mickey Mouse. _______________________________________________________________________ 35. In hot weather, many people enjoy lemonade, which is a drink that is made from lemon juice, water and sugar. _______________________________________________________________________

Một hiđrocacbon thành phần chứa 75% cacbon, hiđrocacbon có công thức hóa học:

Giúp em mình với các cao nhân ơi 😓

Các bạn giúp dùm mình câu này nha Tìm giới hạn các hàm số sau: a/ lim x->1 x^2-2x+1 / x^3-x b/ lim x-> âm vc (x^3 - 2x^2 + 2x - 4) c/ lim x-> âm vc (căn bậc 2 2x + x^2 + căn bậc 3 x^3 - 1) d/ lim x->0 căn bậc 2 4x+1 - căn bậc 3 6x+1 / x^2 Cảm ơn ạ!

Hai dây nikelin cùng chiều dài. Dây thứ nhất có điện trở là 40 Ω, tiết diện 0,3 mm2. Nếu dây thứ hai có tiết diện 0,8 mm2 thì điện trở của dây thứ hai bằng;