lúc 6h một người đi xe đạp xuất phat từ A về B với vận tốc v1=12km/h.Sau đó 2h một người đi bộ từ B đến A với vận tốc v2=4km/h.Biết AB=48km a)Hỏi 2 người gặp nhau lúc mấy giờ.Nơi gặp nhau cách A bao nhiêu km b)Nếu người đi xe đạp sau khi đi được 2 giờ rồi lại đi tiếp với vận tốc cũ thì hai người gặp nhau lúc mấy giờ.Nơi gặp nhau cách A bao nhiêu km

1. quá trình biến đổi khí hậu đang ảnh hưởng sâu sắc đến con người ở các châu lục và hình thành kiểu khí hậu lục địa khô ở châu á em có nhận xét gì về kiểu khí hậu trên . Giải gấp giúp mình nha

khai triển hằng đẳng thức(1/4x^2-2y^2) (1/4x^2+2y^2) Giúp mik với:((

21. the film was too boring to watch till the end. The film……………………………………………………………………………… 22. The house on the corner isn’t cheap enough for us to buy. The house ……………………………………………………………………… 23. It takes me one hour and a half to drive my children to school. I ………………………………………………………………………………………

Mng giúp mình với nha!!! NGHIÊM CẤM:HÀNH VI COPY TRÊN MẠNG HAY CỦA NGKHÁC!

Giúp mình bài 4 SGK Ngữ Văn trang 37 lớp 8 tập 1 với ạ ( mong những bài các bạn tự làm chứ không phải bài đi copy )

Vì đi trọ học xa nên em con rất nhớ nhà , ảnh hưởng tới kết quả học tập . Con hãy viết một bức thư động viên em .

viết các số thích hợp vào chỗ trống 1;5;10;50;100.... hãy giải thích cách tìm số thích hợp đó?

1. Em có nhận xét gì về các hình thưc họn lọc của quy trình sản xuất giống ở cây trồng thụ phấn chéo? 2. Cây rừng có đặc điểm gì khác với cây lương thực, thực phẩm? 3.Trong sản xuất giống cây trồng đã áp dụng hình thức chọn lọc nào?

Question 1. I ______ to the same barber since last year A. went B. have been going C. go D. had gone Question 2. When I met Jim, he__________ from his university already. A. Graduated B. has graduated C. had graduated D. was graduating Question 3. This is the second time I _____________that song. A. am hearing B. have heard C. hear D. heard Question 4. The earth_________on the sun for its heat and light. A. Is depending B. depending C. has depended D. depends Question 5.______ for the fact that he was working abroad, he would willingly have helped with a. If it had been b. If it hadn't been c. Had it been d. Hadn't it been Question 6. I didn’t get home until well after midnight last night. Otherwise, I……..your call. A- returned B- had returned C- would return D- would have returned Question 7.Robert is going to be famous some day. He_________in three movies already. ~ I'm sure he'll be a star. A. Has been appearing B. had appeared C. has appeared D. appeared Question 8- If you………to my advice in the first place, you wouldn’t be in this mess right now. A- listen B- will listen C- had listened D- listened Question 9. Since _______, I have heard nothing from him. A. he had left ​B. he left C. he has left ​ D. he was left Question 10- It would have been a much more serious accident………..fast at the time. A- had she been driving B- was she driving C- she had driven D- she drove Question 11.____________ in Australia now, they would go swimming. A. Had they lived B. Were they to live C. Were they live D. should they live Question 12. If you heat water to 100˚C, it _______. ​A. boil​B. boils​C. will boils​​D. shall boil Question 13.If I _____ that yesterday, I _____ them. A. had discovered/ would inform B. had discovered/ would have informed C. had discovered/ could inform D. discovered/ can inform Question 14.What time would we get there ________ the subway? A. we took B. if we took C. unless we take D. provided that we take Question 15.But for our parents, we_____ successful in life A.will never be B.would never be C.would have never been D.had been Question 16.Tom and Mary ______ for Vietnam tomorrow. A. leave B. are leaving C. leaving D. are left Question 17. Look ! the children _________ their bike A. is riding B. are riding C. will riding D. ride Question 18.The Olympic Games............every four years. A. take place B. takes place C. took place D. is taking place Question 19. The man got out of the car, ________ round to the back and opened the book. A. walking B. walked C. walks D. walk Question 20. It was midnight. Outside it ______ very hard. A. rains​ B. rained C. had rained D. was raining Question 21. I will never talk to you again ___ you apologise to me ____your being rude A. if/ for B.unless/for C.or/of D.whether/or Question 22. If you can give me one good reason for your acting like this, __________this incident again. A. I will never mention B. I never mention C. will I never mention D. I don't mention Question 23. If I ............ you were coming, I ............ you at the station. A. had known/ would meet B. knew/ would meet C. had known/ would have met D. know/ will meet Question 24. I…………you sooner had someone told me you were in hospital. A- would have visited B- visited C- had visited D- visit Question 25. _____________ what you intended that, I would have played that match A. Hadn’t I realized B. were I not realized C. I hadn’t realized D. Had I not realized Question 27. ____________he have free time, he’ll play tennis. A. if B.should C.were D.had Question 28. If you ____________cold, don't open the door. A. feel B.feels C.feeling D.felt Question 29. Be quiet! Someone ______ at the front door. I ______ it. A. is knocking/ will answer B. knocks/ am answering C. has knocked/ am going to answer D. will knock/ have answered