Một người đi xe đạp trên đoạn đường ABCD . Trên đoạn AB người đó đi với vận tốc 10km/h mất 30 phút trên đoạn BC với vận tốc 15 km/h trong thời gian 1h và trên đoạn CD với vận tốc 20 km/ h trong 1h30phút . A. Tính quãng đường AD. B. Tính vận tốc tb người đó trên quãng đường AD

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1. Complete the second sentence so that it has the same meaning as the first one: She and her husband often have quarrels --> She doesn't ... 2. Rewrite each sentence so that the new sentence has a similar meaning to the original one, using the word in brackets: 1. You should check the meaning of new words in a dictionary (look) --> You should ... 2. You ought to stop drinking alcohol (give) --> You ... 3. The flowers you sent to me made the happier (cheered) -->The flowers ... 4. He was born and spent his childhood in a small village (grew) --> He ... 5. I think they will have to stop the workshop soon (close) -->I think ... 6. All the family members don't seem to have a good relationship with one another (get) --> All the family members ... 7. They started this factory 30 years ago (set) --> They ... 8. We don't have any tea left (run) --> We ... 9. I expect to hear from you soon (look) --> I ... 10. When did you begin your journey to Da Lat? (set) --> When did you ... 11. I got some information about wonders of the world on the Internet (found) --> I ... 12. You are walking so fast that i can't follow you (keep) --> You ... 13. She refused the job they offered her (turned) --> She ... 14. They have just published another book for children (out) --> They ... 15. People in the village earn their living by growing rice and raising cattle (live) --> People in the village ... 3. Use the words given to complete the sentences: 1. I/wish/i/studying/a smaller school/fewer students 2. When/we/on holiday/used/go/beach/everyday 3. They/said/they/go/Nha Trang/the following day 4. They/know/how/make/pottery products/from/pots/small jars 5. Her mother/happy/know/that/she/pass/the entrance exam 6. Rice/grow/tropical countries 7. I/look/forward/see/you/again/soon