Một vật sáng AB có dạng mũi tên cao 1m đặt vuông góc với trục chính của một thấu kính hội tụ cách thấu kính một khoảng 4cm.Thấu kính tiêu cự 6cm a) Dựng ảnh của vật AB qua thấu kính b) Tính chiều cao của ảnh và khoảng cách từ ảnh đến thấu kính c) Nhận xét tính chất của ảnh

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II. Choose the best one (A, B, C or D) to complete the sentence. 5.The government has launched a ______ campaign to reduce the number of road accidents A. rout safety B. road safety C. way safe D. lane safe 6.This campaign focused on young road ______ and aimed to raise their about the serious impact of road traffic injuries. A. users-awareness B. using-aware C. users-awaring D. drivers-awareness 7.People need to be aware that the ______ limit must be obeyed on that route. A. speedy B. speeding C. speediness D. speed 8.A driver’s ______ is an official document permitting a specific individual to operate one or more types of motorized vehicles. A. permission B. paper C. license D. certificate 9.Before you drive away, always fasten your seat belt and make ______ all your passengers wear the seat belt correctly. A. calm B. sure C. certain D. guard 10.Now people who drive with children under 8 years old without putting them in safety seats can be ______ up to $25. A. fined B. paid C. punished D. handed in 11. You will be fined if you get ______ when driving. A. drinking B. drink C. drunk D. drinked 12.We are running ______ gas, so we need to stop before we get on the highway. A. out of B. in C. out D. down 13. Not wearing a helmet when driving a motorbike is ______ the traffic laws. A. broken B. break C. breaking D. broke 14. It took me 2 hours ______ my bike to school because of traffic jam. A. to ride B. to drive C. riding D. to rode 15. The vehicles queue around the city during the evening ______. A. rush hour B. traffic hour C. peak hour D. both A and C 16.People have to follow the traffic ______ on public streets. A. regulations B. regulars C. definitions D. conditions 17.We should ______ people to use public transport instead of their personal vehicles. A. courage B. encourage C. say D. show 18. More people own ______ cars and it makes the traffic jams problem become worse. A. public B. his C. private D. common