Cho (O), đường kính AB và d là 1 tiếp tuyến của (O) tại A. Trên d lấy M ( khác A ) và trên OB lấy N ( khác O; B ). Đường thẳng MN cắt (O) tại hai điểm C và D sao cho C nằm giữa M và D. Gọi H là trung điểm của CD. a) C/m: Tứ giác AOHM nội tiếp. b) Kẻ DK song song MO ( K ∈ AB ). C/m: góc MDK = góc BAH và MA² = MC.MD. c) Đường thẳng BC cắt đường thẳng OM tại I. C/m: AI song song BD.

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2. Reading Aisholpan Nurgaiv is 13 years old and lives with her family in Western Mongolia, near China. Her family are farmers and she helps on the farm. She also looks after her little brothers and sisters. Aisholpan has a special pet and hobby. She has a golden eagle and loves training it. Training eagles is an important and popular tradition in Western Mongolia. It is a tradition that is two thousand years old. Aisholpan’s father and grandfather are champion eagle-trainers. Mongolia is very cold. Sometimes temperatures are −40ºC. Aisholpan is shy but she is energetic and goes riding through the snow to the mountains with her eagle on her arm. Sometimes she climbs up mountains and is very patient when her eagle is looking for small animals. It is not typical for a girl to train eagles but after two years of training, she is now a champion. Aisholpan thinks that girls are strong too and, ‘can do anything if they try’. Aisholpan is famous because there is a film about her life with her eagle. She knows presidents and actors but her life is simple. She is happy because now she goes to a good school. Her favourite subjects are biology and science and one day she wants to be a doctor. Read the article again. Are sentences 1–8 ‘Right’ (A) or ‘Wrong’ (B)? If there is not enough information to answer ‘Right’ (A) or ‘Wrong’ (B), choose ‘Doesn’t say’ (C). 1 Aisholpan is a teenager.  2 She lives in China.  3 She is an only child.  4 Aisholpan’s grandfather is a hundred years old.  5 Aisholpan goes horse riding with her eagle.  6 She visits her friends in the mountains.  7 She is shy and patient.  8 Now she goes to a good school in America.  giúp mik vs