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thuthuyn173
2 năm trước
Người ta truyền tải một công suất điện 1000 kW bằng một đường dây có điện trở 10Ω. a. Nếu hiệu điện thế giữa hai đầu dây tải điện là 220V thì công suất hao phí trên đường dây là bao nhiêu? b. Để giảm công suất hao phí đi 9 lần so với TH a thì cần tăng hay giảm hiệu điện thế giữa hai đầu dây tải điện lên bao nhiêu lần? Vì sao?
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I/ Change these sentences into passive voice: (Viết các câu sau sang hình thức bị động) 1) They haven’t finished their work ................................................................................................................................................................. 2) They didn’t pay Jack for what he did for preparing their house ................................................................................................................................................................. 3) The police caught the murder when he was buying a plane ticket for an overseas trip ................................................................................................................................................................. 4) Mai didn’t introduce me to her mother ................................................................................................................................................................. 5) A computer can do these calculations much more easily and quickly ................................................................................................................................................................. 6) A terrible flood has destroyed their house ................................................................................................................................................................. 7) Did they feed Lulu last night? ................................................................................................................................................................. 8) Where will your company send you next year? ................................................................................................................................................................. 9) We must do something before it’s too late ................................................................................................................................................................. 10) They were cleaning the floor when I arrived ................................................................................................................................................................. II/ Rewrite sentences with given words: (Viết câu với từ cho sẵn) 1) How long have you lived in Vinh city ? →When ................................................................................................................................................... 2) He has to finish the essay today →The essay ............................................................................................................................................. 3) Nam said”I must finish all these English exercises this afternoon” →Nam said ............................................................................................................................................. 4) “Can you draw ?”Mary asked me →Mary asked me .................................................................................................................................... 5) The doctor advised me not to work too hard →The doctor suggested. ......................................................................................................................... 6) I can’t get 500 points for TOEFL Test →I wish I ................................................................................................................................................ 7) “Do you go to work on foot this morning?”said Lan →Lan asked me ..................................................................................................................................... 8) Because it is raining hard ,we can’t go out for a picnic →It is raining .......................................................................................................................................... 9) Nga checked the information whether I started learning at the age of 5 →Nga asked me “ ................................................................................................................................ ?” 10) Sales of jeans went up and up →Sales of jeans increased .......................................................................................................................

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