Một bơm nén mỗi lần đưa 10 lít không khí ở áp suất 1atm từ bên ngoài vào một bình có dung tích V = 1 mét khối, đã chứa sẵn không khí như bên ngoài. Sau khi bơm n lần thì không khí trong bình có áp suất 3 atm coi nhiệt độ không đổi tìm n? A. 400 B. 200 C. 300 D. 250

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IV. Write in passive voice. (1.25 pts) 1. Large number of tourists visit these tourist attractions annually. ->…………………………………………………………………………………………….. 2.They built Po Nagar Cham towers to honor the goddess Po Nagar. ->……………………………………………………………………………………………. 3.Tourists don’t visit this museum very often. ->…………………………………………………………………………………………… 4. She bought all this cheese in France. ->…………………………………………………………………………………………… 5. They didn’t invite me to their new year party. ->…………………………………………………………………………………………… V. Matching to make completed sentences. (2 pts) A B 1. If people keep dumping rubbish into the lake, a. the groundwater will be poisoned. 2. If the farmers overuse pesticide, b. if our surrounding environment is polluted 3. Soil erosion won’t happen in an area, c. they will disappear in the future. 4. if we don’t converse the rainforests, d. unless we join hands to protect it. 5. Our health will be badly affected e. the aquatic life will be afflicted. 6. Our environment will be damaged f. floods will be more and more severe. 7. Is we don’t protect the frontier forests, g. if people use more public transportation. 8. The amount of carbon dioxide in the atmosphere will be reduced h. if people practice sustainable agricultural mad use. 1. ____ 2. __________ 3. _______ 4. ____________ 5. ____ 6. __________ 7. _______ 8. ____________ VI. Read the passage and complete the sentences. True (T) or false (F). (1.5 pts) Air pollution is a serious problem in many cities. Motor vehicles, factories and other sources create so much air pollution that it may hang in the air like dirty fog. Air pollution threatens the health of the people who live in cities. City wastes cause water pollution when they are poured into the waterways. These wastes kill fish and make some areas unfit for swimming. In addition, many large cities have difficulties in disposing of their garbage. The amount of garbage grows each year, but places to put it are quickly filling up. Citizens, governments, industries, scientists, and business people must work together in different ways to gradually reduce pollution. For example, most cities have introduced recycling programmes. • 1. Motor vehicles and factories are among some sources of air pollution. • 2. Air pollution doesn’t endanger people’s health in some cities. • 3. Air pollution is the only problem of the environment mentioned in this passage. • 4. Garbage disposal is a problem in many large cities. • 5. Everyone must cooperate to reduce pollution. • 6. We can reduce pollution by recycling programmes only.

I. Multiple Choice. (2 pts) 1. Mary wondered if Neptune __________ larger than Saturn. A.was B.being C.is D. were 2. Three hundred people were left …..by the earthquake. A. homely B. unhomely C. homeless D. homeness 3. There will be a ……..rainstorm next week . A. power B. powerful C. powerless D. powerly 4.If we use water………, more people will have cleaner water. A. care B. carefully C. careless D. carelessly 5. Water pollution make some aquatic animals…….. A. dying B. to die C. die D. died 6. The city has a summer ….. in the park . A. festivily B. festive C. festively D. festival 7.English is an …….. language in Singapore A. office B. official C. officer D. officially 8.She prefers English ……France A. to B. for C. at D. in II. Gerund and Infinitive.(2 pts) 1. My father usually helps me_______ English.( to learn/ learn/ learning/ both a and b) 2. He was heard_______ shout.( to/ of/ by/ at) 3. This student is expected_______ the first winner of the Grand Prix. a. be b. being c. to be d. will be 4. I told her_______ about her wedding; everything will straighten out. a. Don’t worry b. not to worry c. no worry d. not worry 5. May I suggest you let_______ a. Mary doing so b. Mary do so c. Mary does to d. Mary to do so 6. The doctor advised_______ late. a. me not staying up b. me not stay up c. me not to stay up d. I did not stay up 7. Mr. Brown told the schoolgirls_______ in class. a. don’t eat b. not to eat c. eat not d. not eat 8. Try_______ so many mistakes. a. not to make b. not make c. to make not d. make not III. There is one mistakes in each sentence, find out and correct it. (1,25 pts) 1. .As soon as he will come back from his office, tell him to see me. A B C D 2. He regretted not say goodbye to his girlfriend at the airport. A B C D 3. The town we visited was a four-days journey from our hotel, so we took the train A B C Instead of the bus. D 4. Our new neighbors had been living in Paris since ten years before moving to their present A B C D house. 5. The explanation that our teacher gave us was difficult than the one you gave us. A B C D