các bạn giải chi tiết giúp mình với

Ai rảnh chỉ e với ạ!! Cảm ơn trước nha!!

1. a) Tìm số đối của mỗi số nguyên sau: -6 ; 4 ; |-7| ; -(-5) b) Tính nhanh: (15 + 21) + (25 – 15 – 35 - 21) 2.Tính tổng các số nguyên x, biết: a) -3 < x < 2 b) -789 < x ≤ 789 Nhanh nha mn

Cửa hàng buổi sáng bán được 3,76 tấn xi măng.Buổi sáng bán kếm buổi chiều là 1/10 thì cửa hàng còn lại 1,5 tấn xi măng.Hỏi lúc đầu cửa hàng có bao nhiêu tấn xi măng ?

em hãy giải thích nhan đề truyện "Buổi học cuối cùng"

m=50kg s=5m h=1,2m Fe=15N a)Atoàn phần=? F=? b)H=?

IV. Mark the letter A, B, C, or D to indicate the correct answer to each of the following questions. 1. I ____ English for five years. I study it at school. A. have been learning B. have learnt C. learnt D. am learning 2. You can have your book back now. I ____ it. A. have been reading B. have read C. had read D. read 3. You look upset. ____ you ____? A. Are – crying B. Do - cry C. Have - been crying D. Have - cried 4. How many times ____ you ____ that international conference? A. did – attend B. do - attend C. have - been attending D. have - attended 5. I ____ for my math textbook all day, but I ____ it yet. A. have been looking/haven't found B. have looked/haven't found C. have been looking/haven't been finding D. have looked/haven't been finding 6. Mum ____ all morning. She ____ lots of Christmas presents. A. has shopped/has bought B. has been shopping/has bought C. has been shopping/has been buying D. has shopped/has been buying 7. Kevin ____ his homework, but he ____ it yet. A. has been doing/hasn't been finishing B. has done/hasn't finished C. has been doing/hasn't finished D. has done/hasn't been finishing 8. Pete ____ at Midfield Secondary School since 2006, but he ____ music in his lessons twice. A. has been teaching/has only played B. has been teaching/has only been playing C. has taught/has only been playing D. has taught/has only played 9. I ____ the biography of Robbie Williams, but I'm on page 50. A. have read B. have been reading C. had read D. was reading 10. Jimmy can go out when he ____ for the exam. A. has been studying B. has been studied C. has studied D. studied 11. I ____ the latest Harry Potter book all day. I'm dying to know what happens in the end! A. am reading B. have been reading C. have read D. had read 12. So far I ____ any of the exams at school. A. haven't been failing B. hadn't failed C. didn't fail D. haven't failed 13. We ____ our classroom for the upcoming Teachers' Day, but there's still a lot to do. A. are decorating B. decorated C. have been decorating D. have decorated 14. Margaret ____ in the school marathon for charity before. A. has never run B. never runs C. never ran D. has never been running 15. My brother graduated from Hong Kong University of Science and Technology last month and ____ for a job since then. A. has been looking B. has looked C. was looking D. had looked 16. Tim ____ for the scholarship to study abroad in the USA at least twice. A. applied B. is applying C. has been applying D. has applied 17. All the students ____ for their academic transcripts all this week, but they ____ them yet. A. have waited/haven't received B. have been waiting/haven't received C. have waited/haven't been receiving D. have been waiting/haven't been receiving 18. I ____ for the information about the differences between further education and higher education all this morning. A. had searched B. have been searched C. have been searching D. have searched 19. It's the first time you ____ an online course, isn't it? A. had ever taken B. have ever been taking C. ever took D. have ever taken 20. The teacher ____ the speaking task on the board, so now the students are discussing it. A. has already been writing B. has already written C. already wrote D. had already written 21. Sandy ____ his sister since she ____ to university in 2014. A. hadn't seen/went B. hasn't been seeing/went C. didn't see/has gone D. hasn't seen/went 22. They ____ to Spain for an educational exchange and won't be back until the end of this month. A. have gone B. went C. have been going D. is going 23. Poor Tracy! She ____ that essay for hours now and she still ____. A. has written/hasn't finished B. has been writing/didn't finish C. has been writing/hasn't finished D. has written/hasn't been finishing 24. Tom and Mary are still discussing the math exercise with each other because they ____ how to do it. A. aren't working out B. haven't worked out C. haven't been working out D. didn't work out 25. I ____ reading a wonderful book about space travel. A. just finish B. just do finish C. have just finished D. have just been finishing

nhân dân ta thường khuyên nhủ nhau:"thương người như thể thương thân". em hiểu lời khuyên trên như thế nào?

sự giao lưu buôn bán kinh tế tự nhiên

giải dùm em môn sử với ạ em ko hiểu câu hỏi