Cho tam giác ABC vuông tại A, AB < AC. Gọi D, E, F lần lượt là trung điểm của các cạnh AB, AC, BC. a) Chứng minh : Tứ giác FDEC là hình bình hành. b) Chứng minh : AF = DE. c) Gọi K là hình chiếu của điểm A trên cạnh BC, chứng minh tứ giác KDEF là hình thang cân.

Xác định chất tham gia, chất sản phẩm trong sơ đồ phản ứng hóa học sau: Lưu huỳnh + Oxi ---> Lưu huỳnh đioxit Sơ đồ phản ứng hóa học trên được đọc như thế nào?

cho 25 số nguyên trong đó tích của 3 số kì là một số dương . Chứng minh 25 số đó đều dương. giải hộ mình với mình sẽ vote cho thank

I. Chia động từ trong ngoặc: 1,Every day my neighbor (call).......... me on the phone and (complain)......... about the weather. 2,One of the world largest library (be)........... The United States' Library of Congress. It recieves copies of all American books and (have)............. over 1,000 million books. 3, How long your vacation (last).................? -About two months. What you (do)........ during this vacation? -I don't know exactly. Maybe I (go).............. Samson with parents. 4, Mike is a student, but he (not go)................ to school right now because it i summer. He (attend)............ college from September to May every year, but in the summer he usually (have)............ a job at the post office. In fact, he works there this summer. 5, What you (think)........... Tom (do).............. 6, You (do)................... anything next weekend? -Yes, my nephews (come)............. and I (show)..................... them round London. 7, Last night the boy had a good night' sleep. He (sleep)...... nine hours 8, What you (do).......... in your dressing grown? It's 8.00 o'clock. 9, I (not feel)........... very well. I (have)......... an early night. -Oh, dear, I hope you (fell).......... better in the morning. 10, Listen to those people. What language they (speak)......... 11, Yesterday Ba (go)........... to the doctor because he was ill. 12,Before you read a book, you should turn the list of ...... first (contain) 13.Are there any (complain)……….about the service of the hotel? 14. My brother is not very ………..He usually stay at home and reads books in the afternoon.(sport) 15. Their mother is a nurse. She takes care of sick……..in the local hospital.(child) 16. I am not ………in this talk .(interest) 17. Thank you very much for ……… me.(invite) Oh, it's my…………(please). II.Điền từ thích hợp vào chỗ chấm: My room is small and comfortable . I do not share it (1)…….anyone. I arrange the pictures and the furniture differently every few months. This month, my bed is against the wall opposite the door, and there is a mat in front of the bed. (2)…………the right , there is a small bookshelf(3)…….the far corner of the room, and an armchair in the near corner.(4)……….the left of the door, under the window , there is a table and a chair. My pictures are (5)………..the wall opposite the window. III.Dùng từ gợi ý viết câu hoàn chỉnh: 1.Trung/learn/how/the guitar/moment. He/play/fairly well. 2.You/now /every subject/school/be important? 3.Classes/start/7.15/finish/11.45 4.Marie curie/born/Poland/1867 5.Mother/die early/and/father/try hard/bring up/four children. 6.she/learn/read/write/at/age/four 7.School/she/very good/natural sciences 8.Sixteen/leave school/and/go/France/study 9.France/after lectures/spend hours /university library/lab help meeeeeeeeeeeeeeeeeee!!!!! hứa sẽ vote 5+ câu trả lời hay nhất

Lúc 7h một người đi xe đạp từ A đến B, mỗi giờ đi được 10km. Cũng vào lúc 7h đi xe máy từ B đến B, mỗi giờ đi được 26km. Lúc 8 giờ rưỡi hai người gặp nhau. Hỏi khoảng cách từ A đến B dài bao nhiêu km?

những phát biểu sai về vai trò của nước tronh tế bào

Giúp mik vs cần gấp ạ hứa sẹ cho 5 sao ạ

1. We / finish / classes / two hours ago ……………………………………………………………………………………… 2. My parents / give / lovely present / last birthday ……………………………………………………………………………………… 3. I / receive / letter yesterday but I / not / know / who / send / it / me ……………………………………………………………………………………… 4. Lan / make / new dress / last week but it / not fit because it / be / too small ……………………………………………………………………………………… 5. Last weekend / students / class 7A / have / nice trip / Dalat ………………………………………………………………………………………. 6. Last year / Huy / play / games / much , so he / not / pass / her exam ………………………………………………………………………………………. 7.When / he / leave / house / yesterday? ………………………………………………………………………………………. 8. Nam / be / school library / three hours ago / borrow / comics ………………………………………………………………………………………. 9. Mr Nam /learn /English last week but he / not / know / read it ……………………………………………………………………………………… 10. Minh / have / birthday last Saturday / and / invite / lot / friends ……………………………………………………………………………………

Tìm x biết : 5 phần 4x-2 = -1 phần 5-x

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