quãng đường ab dài 85km .một ô tô tải đi tuwg a đến b .sau đó 15 phút một xe khách đi từ b về a, sau khi xe khách đi được 30 phút thì chúng gặp nhau . tính vận tốc của mổi xe ? biết rằng vận tốc của xe khách hơn xe tải 20km/h hộ mình với

giup minh cau c , d nha mng thx a

Các cách chứng minh tiếp tuyến của đường tròn lớp 9 ( full ). Lấy VD minh họa.

mọi người ơi giúp e với ạ, thank mọi người

:_))))))))))))))))))))))))))))))))))))))))))))))))))))))

Vẽ lại ảnh này nhe Ai đẹp choa tlhn Cứ vẽ từ từ Đừng nhanh ko xấu ó

14. Lan enjoys (walk) ____________ on the street to see the falling leaves in autumns. 15. She used to (eat) ____________ chocolate but now she hates it. 16. They (not keep) ________________ in touch with each other for two years. 17. Do you think that (chat) _________________ on the Internet is a waste of time 18. I used (tell) _____________________ folk tales by my grandmother when I lived in the countryside. 19. I ____________________ (just /meet) Ann’s husband. I met him at a party last night. 20. All the students have finished (paint) ______________ the pictures so far. 21. Lots of trains used ____________________ (stop) here, but not many do now. 22. Minh is very hungry now because he (not eat ) ________________ anything since yesterday. 23. I’m looking forward to (watch) ________________ the European Football tournament next week. 24. It takes a long time (learn) ____________________ a foreign language. 25. He (not find) ________________ her phone number yet. 26. Lan spends most of her free time (play) _________________ computer games. 27. She invited us (join) __________________ her family on a trip to Ha Noi. 28. John (use) _______________this motorbike since 2002. 29. Our teacher asked us (prepare) ______________ our lessons carefully. 30. The girl used (write) ______________ to her father when she lived far from him. 31. In the last ten years, life in our city (change) _____________ dramatically. 32. My sister enjoys (read)__________________ about wild animals and natural mysteries. 33. My father didn’t use (smoke) __________________ when he was young. 34. They (move) _____________ three times since they got married. 35. Mrs Thanh suggests (take ) _____________ showers to save water. 36. I used (live) ______________ in the countryside when I was a child. 37.We (not enjoy) __________________ourselves so much for many months. 38. He doesn’t mind (wait) ______ for her. 39. We used (write) _________________to each other every month when we were at secondary school. 40. These flowers are dying. You (not water)___________________ them for ages. 41. My sister prefers (listen)______________ to music to watching TV. 42. He agreed (meet)_______________us at Galaxy Nguyen Du. 43. Nam (not do) _________________his homework yet. 44. I don't mind (ride)________________ a bike to school on rainy days. 45. John managed (contact)________________ his family in England by using zalo.

giúp em kẻ hình với làm phần a, b với ạ T^T

Mn giải thích cho mik từ cái chỗ nhỏ hơn hoặc bằng đó . Mấy cả tìm a b c khi dấu bằng xảy ra .

Ở nước ta, vận chuyển đường ống tập trung chủ yếu ở vùng nào?