Tính toán thiết kế máy biến áp có những thông số sau : Điện áp sơ cấp U1=220V-50Hz, điện áp thứ cấp U2=25V, Công suất máy biến áp Fđm = 70VA. Hệ số lấp đầy lõi thép là KL = 0,9. Số vòng trên V là n=3,8. Mật độ dòng điện cho phép là J =3,5 A/mm^2. Hệ số lấp đầy cửa sổ KL =0,2. giúp ạ

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TIÊT 11 LISTENING HOMEWORK I. Choose the word with the underlined part pronounced differently from the others. 1. A. humour B. rough C. favourite D. rumour 2. A. guitarist B. apartment C. market D.sympathy 3. A. funny B. unselfish C. Minute i D. nothing 4. A. introduce B. motorbike C. gossip D. forget 5. A. time B. trip C. visit D. sing II. Choose the word which is stressed differently from the others. 1. A. favourite B. apartment C.guitarist D. acquaintance 2. A. introduce B. residential C. interest D. understand 3. A. helpful B. friendly C. sociable D. unselfish 4. A. area B. humour C. around D. minute 5. A. college B. guitar C. movie D. family III. Choose the best option to complete the following exchanges. 1. Lisa: --------------------------------------? John: He has got a broad forehead and square face. A. What is Andy like? B. What does Andy like? C. What does Andy look like? D. What is Andy? 2. Mai: What is your best friend like, Minh? Minh: He is -----------------. A. tall B. handsome C. generous D. beautiful 3. Mr Pike: What does your daughter look like? Mr Brown: Oh, she is really --------------------. A. good-looking B. good-natured C. caring D. studious IV. Write meaningful sentences by using the following suggested words. 1/ Daisy IS my close friend. ------------------------------------------------------------ 2/ She/ tall. Her hair/ long/ black ------------------------------------------------------------ 3/ She/ oval face ----------------------------------------------------------------- 4/ She/ caring/ honest ------------------------------------------------------------ 5/ We/ be/ friends/ since last year ------------------------------------------------------------ 6/ She/ good/ Maths ------------------------------------------------------------ 7/ She/ like/ listen/ music ----------------------------------------------------------------- 1. S BE ADJ 2. S HAS/ HAVE / GET + N