Cho đường tròn (O), đường kính AB. Lấy C thuộc đường tròn (O) (C khác A, B). Tiếp tuyến tại A của đường tròn (O) cắt BC tại M. a/ Chứng minh : ABC là tam giác vuông và BO^2 = BC.BM/2 b/ Goị K là trung điểm MA. Chứng minh KC là tiếp tuyến của đường tròn (O) và KO là đường trung trực của AC.

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IV)-Complete the sentences, using “have to” and the verbs from the box in the correct form either positive or negative. open talk stop take decide get up send explain 1. We _________ early at the weekends. (negative) 2. I __________ which job I want before the end of the week. (positive) 3. We _________ the bus into the city center. We can walk. (negative) 4. She ___________ the shop at 9 o’clock every morning. (positive) 5. You _________ quietly in the library. (positive) 6. You _________ the letter to him by post. I will see him tomorrow and I will give it to him then. (negative) 7. You _________ it to me. I understand the problem. (negative) 8. We _________ talking when the lesson starts. (positive) V)-Complete the tips about Vietnamese table manners by filling in each blank with “should” or “shouldn’t”. 1. When having a meal, you ________ pass all dishes using both hands. 2. You ____________ place your chopsticks on the designated chopsticks holder when taking a break to drink or speak. 3. You ____________ stick your chopsticks vertically in the middle of the rice bowl. 4. You ____________ eat directly from the serving dish. 5. You ____________ try every dish that is served before obtaining more of your favourite ones. 6. You ____________ consume only meat, as it is the most expensive ingredient of the meal. 7. You ____________ finish the food put on your plate because this shows respect for the cook and is not wasteful. 8. You ____________ refuse any food offerings despite being full. 9. You ____________ inform the host that you are full prior to being offered another dish. 10. When you finish a meal, you __________ place your chopsticks on top of your rice bowl. Giúp mình với, mình sắp nộp bài rồi!!