Trong 40 kg nước biển có 2 kg muối. Tính tỉ số phần trăm của muối trong nước biển ?

Cho x,y,z dương thỏa mãn:x+y+z ≤1. Chứng minh: 2(x+y+z)+3( $\frac{1}{x}$+ $\frac{1}{y}$ + $\frac{1}{z}$ ) ≥29.

Toán hình nhé mấy anh chị (: Hãy tìm vị trí của 3 điểm A, B, C (có vẽ hình minh hoạ) để: a) Tia AB và tia AC đối nhau. b) Tia BA và tia BC trùng nhau. c) Tia AB, AC không trùng nhau và cũng không đối nhau.

35. I can’t stand people with no……………….of humor. A. ability B. spirit C. keenness D. sense 36. When it rains heavily, John usually…………………..at home. A. stay B. will stay C. stays D. will be staying 37. Finishing his speech,………………………..to make questions. A. the students asked him B. he asked the students C. the students asked D. he asked 38. John…………………anything since yesterday. A. didn’t say B hasn’t said C. hadn’t said D. said 39. Tom…………………….before we arrived there. A. has left B. had left C. will leave D. leaves 40. I didn’t pay attention to the boy. I was busy………………how I would look in the new dress. A. imagine B. to imagine C. imagined D. imagining 41. When I woke up this morning, it…………………… A. rains B. rained C. was raining D. had rained 42. We are too late. The plane………………….off ten minutes ago. A. took B. has taken C. had taken D. was taken I. Give the correct forms of the words in brackets: 1. Would you mind if I asked you some…………………………….questions (person) 2. I’m …………………………….sorry for being late again. (extreme) 3. Don’t put too much……………………………in what the papers say (confide) 4. He’s an……………………………….to his family (embarrass) 5. You need to be more………………………………if you want to become a novelist (imagine) 6. The Beatles were the pop………………………..of the 60’s (idol) 7. Their trip to the countryside was a……………………………..experience (memorial) 8. Your hand should be……………………….washed before you have meals (care) 9. Bi Rain is a………………………….pop star (fame) 10. This…………………………girl was disliked by the rest of the class (sneak) II. Rewrite the sentences so that they are nearest in meaning to the sentence printed before them: 1. Jack left the office before I arrived.  When . 2. During lunch, someone rang the bell.  While . 3. I haven’t been to the dentist for six months.  The last time . 4. She has studied Japanese for 5 years.  She began . 5. He did all his work and then he went home.  After . 6. Steven bought a new motorbike, but first he saved enough money.  After . 7. The guests left and then we tidied the house.  When . 8. I haven’t heard from them for ages.  It’s ages . 9. The postman was bitten by our dog.  Our dog . 10. Whose suitcase is this?  Who does . 11. Alice’s strange ideas astonished everybody.  Everybody . 12. What’s your date of birth?  When ? III. BARE INFINITIVE / TO INFINITIVE OR V-ING (do / to do or doing?) 1. They allowed him (write / to write / writing) to his wife. 2. They let him (write / to write / writing) to his wife. 3. We saw the thief (to run / running) away. 4. Watch that boy (jump / to jump ). 5. The customs office made him ( open / to open / opening) his briefcase. 6. The customs office ordered him ( open / to open / opening) his briefcase. 7. We felt the house (shake / to shake) 8. She could felt her heart ( to beat / beating ) wildly. 9. They left me (wait / to wait / waiting) outside. 10. I caught him ( steal / to steal / stealing ) apples from my garden. 11. I will have you (know / to know / knowing ) that. 12. Just look at the rain (come / to come / coming)down. 13. Do you smell something (to burn / burning)? 14. It’s a pleasure ( see / to see / seeing ) you again. 15. We like our friends (come / to come / coming ) with us. 16. I found him ( work / to work / working) at his desk. 17. It was stupid of her ( make / to make / making) such a mistake. 18. You are very kind (say / to say / saying ) so. 19. I shall be happy ( accept / to accept / accepting) your invitation. 20. She was busy ( practise / to practise / practising ) her piano lessons. Put the words / words in order to make sentences. 1. his offer / it was / you / of / to accept / unwise …………………………………………………… 2. to / It’s / say so / of / kind / you ……………………………………. 3. to make / of her / stupid / such a mistake / it was / ……………………………………………………….. 4. foolish / to agree / of Mr White / it was / to the proposal ……………………………………………………………… 5. Mr Green / to Mr Black / to lend money / unwise / of / it was …………………………………………………………………… 6. the kitten’s tail / of Mary / naughty / to pull / it was …………………………………………………………. 7. of you / to contradict / it was / the professor / wrong …………………………………………………………. 8. careless / leave your umbrella / it was / of you / in the train ……………………………………………………………….. 9. to offer / good / to help / of Mrs.White / it was ………………………………………………….... 10. them / wicked / say / to / is / it / of / things / such

Mn giúp mình với ạ, cảm ơn nhiều nhiều lắmm

I. Choose the word which underlined part is pronounced differently form that of the others: 1. A. finger B. English C. solemn D. thing 2. A. young B. long C. seven D. sing 3. A. bank B. any C. now D. money 4. A. think B. blanker C. hungry D. snow II. Choose the word that has the stress pattern different from that of the others: 5. A. definition B. production C. situation D. politician 6. A. ambitious B. dangerous C. mysterious D. experience 7. A. before B. imply C. countless D. arrive 8. A. promise B. expensive C. constructive D. original III. Choose the underlined word or phrase (A,B,C or D) that needs correcting: 9. The house painted (A) more three years ago, but I’m not going to (B) have (C) it done (D) again for a while. 10. Mike usually (A) drives to work (B), but today (C) he walks (D). 11. My mother makes (A) me doing(B) my homework so (C) I can’t go out (D). 12. He spent (A) most of his (B) time to paint (C) in the studio (D). IV. READING COMPREHENSION: A. Read the passage and choose the most appropriate word for each blank: Janet got married to Pedro last Saturday, and we went to the (13) ……………………., which (14) ……………….place in a lovely little church in the country. Janet, the (14)…………………, wore a beautiful white dress: it had a long train made of silk, and it was carried by a young bridesmaid, who was the daughter of her eldest sister. At the start, her husband – to – be , the (16)……………., was waiting for her at the front of the church. She walked down the aisle to the front with her father, and after the (17)……………….., she came back down again with her husband. 13. A.engagement B. proposed C. marriage D. wedding 14. A. found B. held C. took D. stood 15. A. lady B. groom C. maid D. bride 16. A. male B. man C. groom D. bride 17. A. ceremony B. party C. celebration D. custom B. Read the passage and choose the best answer to each question: UNLUCKY DAY Last Sunday was definitely not a good day for me. It all started when I got into my car and it refused to start. I immediately realized that I had left the lights on and the battery had gone flat. I telephoned my friend George and he came round and helped me start the car. I then drove into town to see a friend. I had arranged to meet him at six thirty, but by the timeI got there, it was ten past seven and my friend was not there. I waited for him for an hour despite the freezing weather, but he didn’t come. When I returned to my car, I saw that someone had broken into it, probably looking for the radio. Luckily, I never leave the radio in the car! There was nothing I could do but get into my car and drive home. Later I spoke with my friend and discovered that he had waited for only half an hour and left. He didn’t even apologise for not waiting for me longer ! 18. Why wasn’t the writer’s car started ? – Because……………… A. The lights had gone wrong B. the battery had gone flat C.it hadn’t been serviced D. the battery had been stolen 19. What was the weather like when the writer waited for his friend? A. cold B. hot C. rainy D. foggy 20. In the writer’s opinion, what did the thief want to steal? A. money B. camera C. radio D. wallet 21. What time did the writer’s friend leave after waiting for him? A. 6:30 B. 7:00 C. 7:10 D. 7:30 22. Which of the following sentences is NOT true? A. A friend of the writer’s helped him start the car B. A friend of the writer’s lived in town C. The writer had waited his friend until 8:10 D. The writer apologized for not waiting his friend for any longer. V. Choose the best answer for each of the following sentences: 23. I haven’t been back to the village where I was born……………..along time. A. during B. since C. ago D. for 24. He pointed………………the spot where the house used to stand. A. off B. to C. for D. into 25. She saw a light ahead. The light was…………..her. A. behind B. beside C. in front of D. above 26. The novel is based on his………………in the war. A. attitudes B. experiences C. situations D. images

Giải giúp mink pt này vs ạ ;))))

Giúp mình nốt bài nhé:(( cảm ơn mọi người rất nhiềuuuuuuu

Làng L ở trong 1 góc nhọn tạo bởi quốc lộ Ox và tỉnh lộ Oy( đều là đường thẳng, giao nhau tại ngã tư O). Từ L muốn mở các đường nhánh dân sinh thẳng LA tới quốc lộ và LB tới tỉnh lộ, đông thời nối luôn 2 điểm giao cắt bằng đoạn đường thẳng AB thì nên chọn các điểm giao cắt A,B như thế nào để tổng chiều dài các đoạn đường mở thêm S=AB+BC+CA

3 + 1/9 + 3/9 + 2 + 5/9 + 3 + 2