Đặt vật AB vuông góc với trục chính của một thấu kính hội tụ có tiêu cự f = 20 cm, cách thấu kính một khoảng d = 30 cm, vật AB có chiều cao h = 4 cm a)Vẽ ảnh A’B’ của AB và nhận xét về ảnh b)Tìm khoảng cách từ ảnh A’B’ đến thấu kính c)Tìm chiều cao của ảnh CHO MIK LỜI GIẢI CHI TIẾT NHÉ ...............HỘ MIK VỚI MIK ĐANG CẦN GẤP.............MIK HẾT ĐIỂM RỒI.................CẦU XIN CÁC CAO NHÂN....

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1. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. According to the passage, city is not a perfect place for__________. A: people who hate competitions B: people who prefer a busy life C: people who look for good jobs D: people who hate busy traffic 2. Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions. (gạch chân a) A: attraction B: frame C: embarrassed D: handicraft 3. Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions. (gạch chân ed) A: carved B: embroidered C: worried D: impressed 4. Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions. (gạch chân a) A: birthplace B: frame C: surface D: layer 5. Mark letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to the original sentence in each of the following questions. Abandoned children should be brought up in orphanages in order to be safe. A: Abandoned children should be brought up in orphanages in order they can be safe. B: Abandoned children should be brought up in orphanages so as to they can be safe. C: Abandoned children should be brought up in orphanages in order that they can be safe. D: Abandoned children should be brought up in orphanages so as that they can be safe.

B1 1.A. nAture B. behAvior C. sepArate D. arrAnge 2.A. City B. Century C. Center D. Caused 3.A.maCHine B. CHeap C. teaCHer D. CHild 4. A . studentS B. lectureS C. speakerS D. nationS B2 1. A . attraction B. occasion C. remind D. adulthood 2. A . describe B. simple C. hobby D. sewage 3. A. garnish B. orchid C. preserve D. accent 4.A. official B. occupy C. technical D. century 5.A. facilitate B. astronomy C. reusable D. indicator B3 1. Do you know the man ___ we met at the party last night ? A. whom B. which C. what D. where 2. it is important to ___ the wonders of the world so that future generations can see them with their own eyes A. destroy B. preserve C. remain D. ignore 3. in ___ students can study a work sector like applied business , design , health , or tourism A. vocational B. academic subjects C. applied approach D. schedule 4. what will you do to earn ___? A. life B. a living C. a job D. a career 5. i wish i could take ___ where i can experience micro gravity A. a parabolic flight B. an ocean cruise C. an express train D. flying course 6. in the near future , a teacher will act more like a ___ than a give of knowledge A. instructor B. facilitator C. speaker D. listener 7. astronomy studies ___ and objects in it like the moon and the sun A. the moon B. the planet C. the universe D. the earth 8. beyond 2030 is a forum ___allows students to share their vision of the future A. who B. it C. which D. and 9. these red buttons are only used in case of ___ A. emergency B. hurry C. rain D. sickness B4 1. i wish i (be) ___ deaf . i don't really want to hear anything about the party 2. the speed limit is 30 miles an hour but Tom (drive) ___ at 50 miles at that time . He shouldn't have been driving so fast 3. if it (rain) ___ could you bring in the washing from the garden ? 4. don't forget (go) ___ to the travel agen't , will you ? the plane tickets need picking up 5. she advised me to consider all the facts before (decide) ___ to accept the job B5 1.After --invented-- --the-- light bulb, Thomas Edison went on to create -many-- other -useful-inventions A B C D B6 1. Tet holiday/ be/one/most important/cleberations/Vietnamese people --------> 2. What/waiting for / you/are ? Upgrade/today/car/your / ! ............................................................................................ 3. Wouldn't / trees/if/it be great/ grew on/ chocolate / ? .......................................................................................... 4. Get / healthy-looking hair/ for you/and /. ............................................................ 5. No frontiers/ your laptop/ for you / and ............................................................................ 6. Because / girls/comfort and style/ love/we our shoes/ into/ design/both/./ ................................................................................... 7. An/you/offer/just for/ exclusive / ! ........................................................................ B7 1. People believe the Perfume Pagoda was built during the reign of Le THanh Tong in the 15th century -----> it is 2. they're telling me that i must make a decision soon . (pressure) ....................................... 3. my sister was offended when she was left out of the english club (exception) ......................................................... 4. the English actor Oliver Reed was often rude to people although he was always kind to animals (being) ........................................................................................ 5. by chance i saw your younger brother yesterday (happened) .............................................................................................. 6. i would like you to help me to put the chairs away (mind) ......................................................................... 7. by this time tomorrow , the president will have the announcemant (passive) ........................................................................ giúp mk vs ạ