một bình chia độ đang chứa345cm3 nước. Người ta nhúng chìm hoàn toàn vào bình một quả cầu đặt nặng 5150g thì mực nước trong bình chia độ lúc này dâng lên đến vạch 845cm3. Biết rằng khối lượng riêng của vàng là 19300kg/m3 và khối luongj riêng của đồng là 8900kg/m3. a) Tính thể tích của quả cầu? b) Hãy xác định khối lượng riêng của chất quả cầu? Và em hãy cho biết quả cầu này làm bằng vàng nguyên chất hay đồng nguyên chất hay quả cầu đó có vàng pha lẫn với đồng?

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Ko spam nha , câu hỏi đây : B.READING: (2,5p) I. Read and tick True (T) or False (F): (1,25p) My name is Quang. I am in class 6A1 at Nguyen Du School. It is a small school on Nguyen Du street. My classroom is on the second floor. There are 40 students in my class. My form teacher is Miss Mai. She teaches us English. All of my classmates are really kind and hard-working. We always finish all homework at home. Every day, we start classes at seven o'clock and have a 20-minute break at thirty-five past eight. My school has a small schoolyard so the students usually stay in class or sit in the canteen at break time. After that, we are back to our room and finish class at half past eleven. I. True or False statements: (1,5 p) 1. Quang's school is small. 2. There are forty students in his class. 3. Quang and his classmates always finish all homework at home 4. Quangs classes start at seven. 5. Quang's school has a big yard. 6. Quang finishes classes at half past ten. II. Answer the questions: (1,0 p) 1. Which floor is Quang's classroom on? 2. What subject does Quang's form teacher teach? 3. Is Quang's school big or small? 4. What time does Quang have break ? C. WRITING: (2,5 p) I. Rewrite the sentences, use the word in parentheses: (1,25 p) 1. There is a fridge, a table, four chairs in Thu's kitchen.- Thu's kitchen 2. My school does not have any gardens.- There 3. Does your house have three bathrooms?-Are there 4. The desk is in front of the chairs.-The chairs 5. The cat is in front of the TV-The TV II. Write a short paragraph (5 sentences) to describe your house basing on the questions below (1,25 p) 1. Where is it? What does it look like? 2. How many rooms are there in the house? 3. What furniture does the house have? 4. What do you like best about the house?/ Why? D. VOCABULARY and GRAMMAR: (2,5p) L Circle the word which has underlined part pronounced differently from the others: (0,5 p) 1. A. some II.Choose the best answer A, B, C or D to complete the sentences: (1.5 pts) 1. What is this? - It is 2. Minh is very A. talkative 3. The TV is 4. An's room is D. toilets B. chairs C. lamps B. post C. come D. Monday 2. A. books D. X C. some B. an armchair. A. a He always has a lot of new ideas. C. creative B. next D. friendly C. between B. boring to the table. A. near D. opposite because there are a lot of clothes on the floor. C. bright D. beautiful C. What B. untidy is Mai?- She is in the kitchen. A.Who A. new D. Where B. When 5 in Western countries. 6. We find no A. houses B. flats C. apartments D. stilt houses III. Supply the correct form of the verbs: (0,5pt) 1. Look! The students (play) 2. Mr Hung usually (not ride) baseball in the park. his bike to school. DE 4