Nguyên tử của nguyên tố X có tổng số hạt là 58. Tổng số hạt mang điện nhiều hơn tổng số hạt không mang điện là 42. Nguyên tố X có điện tích hạt nhân là .. a.19 b.19+ c.19 d.20+ Trình bày cách làm nhé

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Exercise 1: Complete the sentences, using the correct form of the verbs in the box. 1. I requested that everyone in my class (attend) __________my presentation. 2. I suggest that we (focus)__________on its advantages and disadvantages. 3. Our Geography teacher also advised that we ( talk)__________about issues that are familiar and important to our classmates. 4. The teacher demanded that the classroom (clean) __________ immediately. 5. My father insists that my brother (work) ____________ on the farm. 6. The governmentdemanded that rural people ( allow) _________________to live and look for jobs in big cities. 7. The government urged that people ( not/ waste) ______________natural resources. 8. His parents insisted that he ( find)____ ____________ a job and settle down in a big city. 9. My mother recommended that I (follow) _______________in my grndpa’s footsteps and ( become) _________ a teacher 10. I suggested that he ( move) ____________to the city for a better health care. Exercise 2: Complete the sentences, using the correct form of the verbs in brackets. 1. It is important that he (get) ___ gets___into a good university. 2. It is vital that people (allow) __________where to live. 3. It is crucial that urban people (not look down on) __________ rural people. 4. It is recommended that the presentation ( be) __________ no more than 15 minutes. 5. It's important that we ( talk)__________about how developed countries have solved the urbanisation problems. 6. Is it really necessary that we ( include ) _________ new information in the conclusion? 7. It is necessary that he (find)__________ the books. 8. It is important that you ( remember) ___________ this question. 9. It is important that the government (encourage )______________more investment in rural areas. in rural areas. 10. It is desirable that people in rural areas (have) ________ access to modern facilities and technology