Cho một tia sáng đi từ môi trường có chiết suất 1,4 m không khí A. Tính gốc sự hạn phản xạ toàn phần B. Hãy cho biết khi góc tới y = 20 độ thì đường truyền tiếp theo của tia sáng như thế nào? Giúp em vs

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I, Multiple - Choice: 1, She gets up at 6 and meditates ____________ an hour before going to work. A. during B. while C. for D. through 2, He ____________ robbed as he was walking out of the bank. A. had B. did C. got D. were 3, Three years ago, my father ____________ with cancer. A. was diagnosed B. had diagnosed C. diagnosed D. was being diagnosed 4, She was working on her computer with her baby next to ____________. A. herself B. her C. her own D. hers 5, Police arrested a man late last night in connection with the murder. Police expect to charge the ____________ later this morning. A. guilty B. suspect C. condemned D. arrested 6, Marie Curie, one of the best-known ___________ in working with radiation, died in 1934. A. debutants B. revolutionaries C. pioneers D. rebels 7, No pharmaceutical compounds have proven effective _______________ neurons or helping the body establish new neural pathways. A. in permanently restoring B. permanent restoration of C. at restoring permanence of D. at permanent restoration in 8, John: "Do you know when Professor Smith's expected to give us our grades?" Jessa: "I'm certain she'll do it ______________.” A. as soon as she's able B. she's able to do it soon C. soon she's able to D. however she's soon able to 9, The comparison to others as a ______________ for social class continues and is being driven by a variety of factors, including prolific advertising and easy credit to _______________ consumers. A. guideline - lobby B. benchmark - endorse C. pattern - hype D. point - entice 10, _______________, the same students who participate in the program in winter should continue to work on the project in spring, to ensure continuity. A. Ideally B. Promptly C. Afterwards D. Beforehand

Read the letter and choose the best answer from A, B, C or D. Dear John, How are you ? I’m still working on the farm, but fortunately I am going to leave here at the end of winter. Let me tell you why. We often have a terrible time every year. Thousands of insects come and eat many of the crops in the fields. The farmer is very worried because he thinks the insects will come again and destroy all the crops. He becomes so worried that he will let others buy the farm next week, and that is why I have to leave here. Soon I have to look for another job. Do you think you could help me find one? I like working on farms so if you know anyone who needs a hard worker, please recommend me to them. I know that you are very busy at the moment and that you don’t have much free time. But I really hope you can find time to help me. I don’t know what else to do. If I can’t find a job, I’ll have to go back home and stay with my parents. I know they will be very sad if I do that. They are old and they don’t have much money. They can’t support me as well as themselves. Love, David 1. At the end of the month, David is going to _________ A. work on a farm. B. start a new job. C. leave the farm. D. buy a farm. 2. What will the farmer do next week ? A. He will destroy his crops. B. He will sell his farm. C. He likes many insects. D. He will become very worried. 3. At the moment John is __________ A. working on the farm. B. very busy. C. helping David. D. living with his parents. 4. If David can’t find a new job, he will go home and __________ A. support his parents. B. work on his parents’ farm. C. live with his parents. D. make his parents rich. 5. How does David feel at the moment? A. He feels very happy. B. He feels angry. C. He feels ill. D. He feels sad.