Một hợp chất B có công thức dạng M2X có tổng sốhạt cơ bản trong phân tửlà 140, sốhạt mang điện trong phân tửnhiều hơn sốhạt không mang điện trong phân tửlà 44, nguyên tửM nhiều hơn nguyên tửX là 11 proton. Xác định CT của B?

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1. Churches, temples and pagodas are places of _________________ A. friendship B. worship C. warship D. scholarship 2. Visitors can really enjoy the peaceful ___________________in Vietnam. A. impression B. expression C. religion D. atmosphere 3. Since 1960 jeans have become more and more ________________ with students. A. common B. popular C. famous D. familiar 4. The Singaporean ________________is Singapore dollars. A. currency B. capital C. language D. climate 5. The United States has a _______________ of around 260 million. A. population B. separation C. addition D. introduction 6. The word jeans comes from a kind of _______________ that was made in Europe. A. iron B. glasses C. wood D. material 7. They have added these _______________ to the ao dai. A. symbols B. fahion C. clothing D. patterns 8. For a long time, the ao dai has been the _______________of poems, novels and songs. A. uniform B. tradition C. subject D. symbol 9. What do you do to _____________________your friends when they fail? A. encourage B. embroider C. wear D. call 10. Today, jeans are ______________________all over the world. A. famous B. popular C. traditional D. wide 11. In the 1980s, jeans finally became high _____________________ clothing. A. fashion B. fashionable C. fashionably D. unfashionable 12. Maria and Van write to each other twice a month. They are ___________________. A. pen friends B. pen names C. pen pals D. A & C are correct 13. They have ____________________for nearly two year, but this was their first meeting. A. talked B. written C. corresponded D. spoken 14. Nguyen Du is considered one of the greatest Vietnamese _________________ A. poems B. poetry C. poets D. poetics 15. Their houses are ______________ situated near the beach. They can go swimming every day. A. convenience B. inconvenient C. conveniently D. inconveniently 16. The English 9 textbook _____________________ten Units. A. comprises B. consists C. divides D. depends 17. The new uniform is very _____________________for the kids. A. traditional B. official C. compulsory D. convenient 18. Many designers took ______________________from Vietnam’s ethnic minorities. A. friendliness B. impression C. inspiration D. fashion 19. Nowadays, Japanese wear kimonos on holidays and on special ________________. A. education B. tradition C. occasions D. fashions 20. Many schools have changed the styles of their uniform to make it more comfortable and ____. A. unfashionable B. unique C. economic D. inconvenient