Một nguyên tử X có tổng số hạt là 46, số hạt không mang điện bằng số hạt mang điện. Tìm số hạt mỗi loại?Viết kí hiệu nguyên tử của Z?

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I. Choose the correct answer: 1. There used to ________ a movie theatre here, but it closed a long time ago. A. be B. to be C. being D. been 2. The children are playing ________in the school yard. A. happy B. happiness C. happier D. happily 3. I wish they ________here tomorrow. A. will come B. would come C. came D. to come 4. David ________write the letter to me last year. A. is used to B. was used to C. used to D. used 5. It is difficult ________English in some weeks. A. to speak B. speaking C. speaks D. speak 6. Hoa is ________English for her work. A. to study B. studied C. studying D. study 7. He arrived in the UK ________Monday evening. A. in B. at C. of D. on 8. Let's ________ to the zoo. A. going B. to go C. go D. goes 9. I am looking forward to ________you. A. see B. to see C. seeing D. saw 10. He ______with his friends in an apartment in Ha Noi since last week. A. living B. has lived C. lived D. live 11. We come to USA ________English. A. study B. learning C. to learn D. studying 12. We wish you ________us someday. A. visit B. will visit C. visited D. would visit II. Give the CORRECT FORM of the word: 1. The Era Town is ______________ into 4 buildings. (separate) 2. Maryam was really ______________ by the beauty of Ha Noi. (impress) . 3. The United States has a ______________ of around 250 million. (populate) 4. Vietnamese people are very _________________ (friend) 5. Vietnam has a ___________________climate with two main seasons.(tropic) 6. English is a ______________ subject at school.(compel) 7. Art and P.E are _______________subjects for children . (option) 8. English is the _______________ language of Singapore. (office) Giúp em với,em cảm ơn ạa!