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eumenides
2 năm trước
Kim loại X có 3 đồng vị, tổng số khối là 75. Đồng vị thứ nhất chiếm 79%, đồng vị thứ hai chiếm 10%. Đồng vị thứ ba nhiều hơn đồng vị thứ nhất 2 nơtron. Tìm số khối mỗi đồng vị biết nguyên tử khối trung bình của X là 24,32
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I. Verb forms: 1. I guess I ( finish ) ............................. my assignment for this semester on time. 2. They have bought a couple of tickets and they ( see ) ...................................... their favorite film at the cinema. 3. Do you know that John has been in hospital ? – No, I don’t. I ( visit ) ............................ him tomorrow. 4. Mai: This bag is too heavy ! – Nam: Don’t worry. I ( carry ) .................................... it for you. 5. . Why is Sheila getting a passport ? – She ( live ) ...................................... in Spain for a year 6. Look at the sky. It ( rain ) ................................... tomorrow. 7. Tom: Where you (go) ___________ for your next holiday? ( Where have you arranged to go?) Ann: I don't know yet but we probably (go) ___________ to Spain. 8. We (have) ________ a drink with Peter tonight. (He has invited us.) It's his last night; he (leave)_______ tomorrow. 9. I (see) ___________ my bank manager tomorrow. (I have arranged this.) I'm going to ask him for a loan but I expect he (refuse) ___________. 10. Take an umbrella; it (rain) ___________. 11. Where you (go) ___________ this evening? ~ I (stay) ¬¬¬¬¬¬¬¬¬_______at home. I (write) ___________some letters. 12. . Human body ( can / support ) ................ by a spine 13. A box full of chocolate ( send ) ............... to him yesterday. 14. . More than 10 pages ( type ) ..................... so far. 15. Every day, the dishes ( wash ) ......... by Jane but today the washing-up ( do ) ....... by Jame

II. Writing: Passive voice: 1. Tom delivers the mail every day …………………………………………………………………………….. 2. Somebody calls the president every day ……………………………………………………………………. 3. My father gave me a new shirt………………………… 4. Weeds cover the riverbank………………………………………………………………………………….. 5. . John is calling the other members ……………………………………………………………………………. 6. Somebody has taken my briefcase …………………………………………………………………….. 7. She finished the report at noon ………………………………………………………………………………. 8. The police have arrested five suspects …………………………………………………………. 9. They are going to decorate the room next week……………………………. 10. She is going to tell a story……………………………. 11. . John will receive the papers tomorrow……………………………… 12. Somebody will call Mr. Watson tonight ……………………….. III. Pronunciation 1. A. proofs B. books C. points D. days 2. A. helps B. laughs C. cooks D. finds 3. A. neighbors B. friends C. relatives D. photographs 4. A. snacks B. follows C. titles D. writers 5. A. streets B. phones C. books D. makes 6. A. cities B. satellites C. series D. workers 7. A. develops B. takes C. laughs D. volumes 8. A. phones B. streets C. books D. makes 9. A. proofs B. regions C. lifts D. rocks 10. A. involves B. believes C. suggests D. steals IV. Stress 1. A. alternative B. bacteria C. respiratory D. scientific 2. A. acupuncturist B. circulatory C. ineffectively D. vegetarian 3. A. ailment B. disease C. pultry D. nervous 4. A. digestive B. intestine C. condition D. evidence 5. A. internal B. skeletal C. therapy D. willpower

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