Cho d1: x+2y-3=0 và d2: 3x-y+1=0. Mệnh đề nào đúng? A. d1 và d2 vuông góc B. d1 và d2 trùng nhau C. d1 và d2 cắt nhau D. d1 và d2 song song

Em hãy viết những hiểu biết của em về covid19 và cách phòng chống bênh (Viết thành một đoạn văn ngắn)

1 xe máy chuyển động đều , lực kéo của động cơ là 1200N. Trong 1 phút, công sinh ra là 780000J. Tính vận tốc chuyển động của xe

14 người làm một công việc phải mất 10 ngày mới xong.Nay muốn làm trong 1 tuần thì cần bao nhiêu người làm?

Mn giúp mik với toán ngu như bò nên ko biết! Giải hết nha!Gấp lắm xy-3x=-19 3x+4y-xy = 16 (x-3).(y+5)=-17 (x+1).(xy-2)=11 xy-7x+y=-22 xy-5y-2x=-41

1. ............................ (you/have) a nice time in Rome? 2. ............................ (you/finish) your homework yet? 3. He (be)........................ at his computer for six hours. 4. How many people (die)................... in the fire yesterday? 5. I (receive)....................... a postcard from Jane yesterday. 6. I (never/be).................. sailing, what’s it like? 7. It was late. Most of the shops (close)..................... . 8. It (rain)...................... when I got up this morning. 9. Janet (start)................... a new job in September. 10. Nelly (have) ........................ a great time in New York at the moment. 11. She was cooking dinner when we (arrive).................... . 12. She (just/come) ....................... back from a Mediterranean cruise. 13. When I got the airport I realized I (forget)....................my passport. 14. As soon as they (arrive).....................we had dinner. 15. When they were driving home last night they (see)..............a terrible accident. 16. Who (Mandy/talk)..... …. ..........to at this moment? 17. What would he do if he (be)………..……. there? 18. I am very sorry but I (not finish) …………….……. reading the book yet. 19. She (be)…..………. ill since last Monday. She won’t be able to go to the sea-side next week-end. 20. They were going to town when I (see)………….. them this morning. 21. If I (bump) ………….. into a ghost, I think I would run away fast or scream. 22. We know he (buy)………..…….. a new house in a small lane quite recently, but we don’t know whether he has sold his old house. 23. I have never seen him again since I (leave)…………… Australia in 1964. 24. Who is this lady? She (move)…………… into No 4 last month. 25. This hotel is empty, it (not live)…………..…. in for a long time. 26. Yesterday afternoon he (have)……..……… a nap in the garden chair when a boy dropped a ball on his head. 27.It’s the last time I …………….(eat) this. 28. This is the worst storm I ……………(ever see). 29. It is the first time I ……………………(ever see) such a beautiful girl. 30.After John………………… (wash) his clothes, he (begin) ………….to study. 31.She came into the room when they ……………….(watch) television. 32.As soon as we find another apartment, we ………………. (move). 33.She …………… (play) the piano when our guests ………… (arrive) last night. 34. My mother ………… (come) to stay with us next weekend. 35. Violets ……….. (bloom) in the spring. 36. We …………….. (not live) in England for the last two years. 37. I didn’t know what time it ……….. (be), so I ……….. (turn) on the radio. 38. She says that she ……….. (live) in the country when she ……….. (be) a child. 39. When the teacher came in, the pupil ……………... (play). 40. Mary ____________(not/eat) meat. She is a vegetarian. 41.They (go) ___________home after they (finish) _____________ their work. 42.In my country, it often (snow) ________a lot in winter. 43.My father _________(be) an engineer. He __________(work) for the company. 44. She (win) ________ the gold medal in 1986 45. Mary and Mr. Steve ________(come) from england. They _______(be) my close friends. 46.What time you _______________(have) lunch everyday? 47.When he came to the stadium, the match (already/ begin)_______________. 48.She ________(run) downstairs and opened the front door. 49.It __________(rain) a lot yesterday evening, so I ________(get) wet. 50.I _____________(just/finish) writing this book . I feel very happy. 51.Yesterday, John (go) ______________to the store before he (go) ____home. 52.He has written the report for three days. He ________________(write) its conclusion now. 53.Peter and I _____________(be) in front of the computer since 7 o’clock. 54.She used to be a winner. She __________(win) the first prize five years ago. 55.We ____________(fly) to New York since last summer. 56.Before I (watch) __________TV, I (do) ________________ my homework. 57.She ________(like) cooking. She ____________(cook) now. 58.She ______________(learn) piano for three months. 59. ______________you (receive) _________ a letter from your old friend last week?.

Một đội công nhân phải làm 1 số sản phẩm theo đơn đặt hàng, dự định mỗi ngày làm ra 40 sản phẩm thì sẽ hoàn thành. Khi thực hiện, mỗi ngày lại làm được 52 sản phẩm, vì vậy đội không những làm xong trước 2 ngày mà còn làm thêm được 4 sản phầm nữa. Nếu gọi tổng số sản phẩm mà đội phải làm theo đơn đặt hàng là x () thì phương trình của bài toán là:

Bài 3 Viết số tự nhiên nhỏ nhất có 6 chữ số sao cho số đó : chia hết cho 3 Bài 4: Có bao nhiêu số tự nhiên có 3 chữ số mà chia hết cho 3

1 which Ace question words 2 which sentence is true 3 mrs mai anh lives in the country.......... Is very rich 4 which sentence is true 5 which sentence is false 6 what kind.......... Film do you enjoy 7 Minh 'S friends.......... Comedies 8cartoon means 9 which question is true 10 fird ''ed" with the sound "/id/?

mn giúp tui nha tui choa mn 30 điểm lun :V