cho hệ pt (m-1)X-mY=3m-1 2X-Y=m-5 tìm m để pt có nghiệm duy nhất (X;Y) mà P=$X^2$ +$y^2$ đạt giá trị nhỏ nhất

Tại sao có thể nói 30/4/1975 là mốc quan trọng trong lịch sử dân tộc ta?

Cho PTHH: Mg(OH)2 + 2HCl -> MgCl2+2H2O Nếu có 4,75 g MgCl2 được tạo thành . Hãy tính a, Khối lượng Mg(OH)2 đã phản ứng b, Khối lượng HCl phản ứng

Vẽ chibi Mk đặt cho các pạn rùi bây h pạn nào có tâm đặt choa mềnh xin 1 câu đuy please

Cho 2,7 g kim loại nhôm tác dụng hoàn toàn hết với axit sunfuric H2SO4 tạo thành muối nhôm sunfat A2(SO4)3 và giải phóng khí hidro . Tính a, Khối lượng muối Al(SO4)3 và khối lượng H2SO4 b, Thể tích khí hidro thoát ra đktc.

Giúp với nhanh nhaaaaaaaaa............

Question 1 :Tsunami is one of __________ natural disasters. A. worse B. worst C. worse than D. the worst Question 2: Last night’s storm caused a lot of __________ to people in that area A. droughts B. forests C. damages D. volcanoes Question 3: Vietnam has just overcome a devastating forest __________ in Ha Tinh. A. fire B. rage C. trap D. thing Question 4: Japan suffers from a large number of __________ every year. A. typhoons B. workers C. eruption D. earthquakes Question 5: The fire was raging so fiercely that the rescue workers found it hard to put it __________. A. down B. out C. off D. with Question 6: There have been some __________ eruptions in this area for the last 10 years. A. volcanic B. scattering C. homeless D. disastrous Question 7: They are trying __________ residents from the flooded area. A. evacuate B. evacuating C. evacuated D. to evacuate Question 8: Have you ever heard __________ mudslide in mountainous area? A. of B. on C. about D. with Question 9:Many buildings __________ in the earthquake and many people have been trapped there. A. collapsed B. collapses C. collapse D. collapsing Question 10: After the tornado, a great number of people are made __________. A. shaking B. homeless C. raging D. volcanic Question 11:We can see pieces of buildings __________ on the ground A. scatter B. to scatter C. scattered D. scattering Question 12: Up to now, the number of __________ is still an estimate. A. victims B. rescuers C. trapers D. homeless Question 13: __________ happens when there is not enough water for farming and drinking. A. disaster B. mudslide C. drought D. trap Question 14:My little sister is afraid of __________, so when there is a bad storm she always hides. A. lightening B. collapsing C. shaking D. scattering Question 15: Last Sunday we wanted to go skiing, but we couldn’t because in the mountains there was an __________. A. earthquake B. drought C. flood D. snowstorm

Giúp em với ạ 😥 em đang cần gấp I.Điền cụm động từ sau vào chỗ trống: Go on cross out. Come across give up Take off. Break into. Set up. Carry out. Cut down blow up

Use past simple or present perfect 1. ...... Helen ever...........(try) sushi ? 2. I..........never..........( be ) to Paris 3. This year I........( travel ) to Athens 3 times so far 4. Paul and Judith........( be ) married since 1998 5. ...........you.........( finish ) your homework yet ? 6. When........... you.......... ( come ) to Greece 7. They..........already........... ( leave ) the train station 8. How long........you...........( know ) Jonathan ? 9. ...........yoy........... ( read ) " Harry Potter " when you were on holidays ? Giúp vs TT

V. Give the correct form of verbs 1. She ( come )…………….. to Hue two weeks ago 2. I ( send )………………….. the letter to my friend tomorrow. 3. He ( work)………………in that company for 5 years 4.She ( graduate)…from Ha Noi national university last year 5. Tom ( play)…………… football every afternoon 6. Lan ( cook)………… in the kitchen when he came in 7.You ( sleep ) ……………………so far ? I ……………( ring ) the bell for the last twenty minutes. 8. If Mai wants ( attend)…………………… the course ,She must (pass) ……………………the test 9 Mary ( lose ) …………………her hat and she ( look ) …………for it until now. 10.I ( see ) ………………… that film several times because I like it. 11. We often( help)………… him with his homework 12.If Mary (not feel) better tomorrow, she will see a doctor 13.My brother( not buy)………… a new bicycle since He(break)…………… the old one last month. 14. I ( not have) ………………a good meal for a long time. I now feel very tired 15. She ( come )…………….. to France two weeks ago 16. Jack (go) …………………to Paris for a holiday. He (not be)…………… there before. 17.He( write ) ……………… a novel for two years, but he ( not finish ) …………………… it yet. 18. If I (be)…………… you, I (tell)…………….... the truth. 19.Her grandfather ( die) …………….20 years ago. She………….. never( meet)………… him 20. If you have finished the report, let’s (go)……………… for a walk. VI. Rewrite each sentence, beginning as shown, so that the meaning stays the same. 1. We have learnt English for 4 years We started……………………………………………………………………. 2. They have worked in that factory since 2001. They began…………………………………………………………………… 3.I haven’t meet her for two years. It is two years.……………………………… …………………… 4. I haven’t seen her before. This is the first ……………………………………………………………..… 5. My father started to give up smoking last year. My father has……………………………………..…………… 6. I last saw her 10 years ago. I haven’t …………………………………………………………….. 7. When did you start to listen to classical music ? How long……………………………………………………………. 8. How long have you taught English here ? When………………………………………………………………… 9 We didn’t see her father a long time ago. We have not ………………………………..…………………….. 10.It is three years since I last saw him. I haven’t ……………………………………………………………………..… 11.This is the first time I have eaten this kind of food. I have not………………………………..………………………………………. 11 If I were rich, I would help you. Were………………………………..………………………………………. 12.If I had known her, I would have made friend with her. Had………………………………..………………………………………. 13.If you should run into Peter, tell him to call me. Should………………………………..………………………………………. 14. If there were no water, life wouldn’t exist. Without………………………………..……………………… EX6 .Put the verbs into the correct form, present perfect or past simple. 1. I don't know where Amy is. Have you seen (you/see) her? 2.When I (get)………….. home last night, I (be) …………….very tired and I(go) ………straight to bed. 3.Your car looks very clean (you/wash) ……………………….it? 4.George(not/be) ……………………………very well last week. 5.Mr. Clark (work)……………………… in a bank for 15 years. Then he gave it up. 6. I don't know Carol sister. I (never/meet)………………………… her.