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GIẢI BẰNG CÁCH LẬP HỆ PHƯƠNG TRÌNH Hai vòi nước cùng chảy vào một bể cạn thì sau 6h40 phút sẽ đầy . Nếu chảy một mình thì vòi thứ hai đầy bể nhanh hơn vòi thứ nhất là 3 giờ . Hỏi mỗi vòi chảy một mình thì sau bao lâu sẽ đầy bể
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III. Choose the correct option A, B, C or D to complete the sentences. (2,5ps) 1. ______ the traffic was bad, I arrived on time. A. Despite B. In spite of C. However D. Although 2. It takes me two hours___________ that letter. A. to write B. write C. writing D. for writing 3. I’m tired of _______ nothing to do at home. A. to have B. have C. having D. had 4. Please tell him to ______ the light. It is getting dark. A. turn on B. turn up C. turn over D. turn off 5. I am sure I locked the door. I clearly remember ______ it. A. to lock B. to have locked C. locking D. lock 6. We didn’t go out ______ it was raining. A. although B. because C. in spite of D. despite 7. An is a hard-working student. I think An___________ pass the exam easily. A. would B. has C. was D. will 8. In order to save energy, don’t forget to ______ the lights before you leave. A. turn B. turn on C. turn off D. turn of 9. The energy consumption__________ as much as possible. A. will reduced B. will be reduced C. be reduced D. reduced 10. My father ______ a lot last year but this year he doesn’t any more. A. used to smoke B. smokes C. gets used to smoke D. smoking I. Read the passage and tick () True or False. (1,5ps) Energy is one of the problems that many people are interested in. It is not an unfamiliar word. It is heard, said, discussed day after day. It is close to everyone’s daily life. You turn on a lamp and it is energy that gives you light. You turn on a TV and it is energy that gives you pictures and sound. You ride a motorcycle and it is energy that gives you movement. You cook your meals and it is energy that gives you heat to boil rice. The problem is that the demand for energy is rising and that the price of energy is getting higher and higher. The supply of energy on earth is limited. It cannot provide us forever. The shortage of energy in the future is inevitable. Therefore, saving energy is a must if we want to continue to live in a safe and sound world. * Notice: familiar: thân thuộc demand: nhu cầu inevitable: chắc chắn xảy ra Statements True False 1. Many people aren’t interested in the problems of energy. 2. The word “energy” is familiar and close to everyone’s daily life. 3. Energy is heard, said, discussed day after day. 4. We can’t watch TV without energy. 5. The supply of energy on earth is unlimited. It can provide us forever. 6. If we want to continue to live in a safe and sound world, we have to save energy

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