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ngogiaan2007
2 năm trước
cho tam giác ABC vuông ở A có góc C +60 độ tia phân giác của góc BCA cắt AB ơ E kẻ EK vuông góc với BC (K ∈ BC ) Kẻ BD vuông góc với tia CE (D ∈ CE) Chứng minh : A) tính CK ⊥ AK ; B) EC =EB và KC =KB C) EB > AC D) ba đường thẳng CA ,BD và EK cùng đi qua một điểm
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Giải hộ em với ạ, em đang cần gấp 1. Read the passage. Circle A, B or C to answer each question. First explorations into the planets Human’s dream of stepping into the outer space has been long ago and Jules Verne - afamous fiction writer of the 19thcentury was the first to describe such journeys.However, it was not until 14 September 1959 when the first artificial object - Lunar 2 -reached the moon. It was a journey of around 36 hours. Then on 3 February 1966 Luna9 - an unmanned space mission - achieved a soft landing on the moon and transmittedphotographic data to Earth. Lunar 10 - a robotic spacecraft mission entered lunar orbiton April 3, 1966. On 20 July 1969, the first manned landing on the moon was made byNeil Armstrong. After his journey, a series of journeys to other planets were made.The first flyby - the flight of a spacecraft near a planet to record data - of Venus wasmade by Mariner 2 in 1962. Other flybies include that in 1965 for Mars by Mariner 4,1973 for Jupiter by Pioneer 10, 1974 for Mercury by Mariner 10, 1979 for Saturn byPioneer 11, 1986 for Uranus by Voyager 2, 1989 for Neptune by Voyager 2. 1. Jules Verne was the first ______. A. to dream of flying into space B . to enter the moon C. to describe space journeys 2. Lunar 2 was the first artificial object to ______. A. orbit the moon B. reach the moon C. land on the moon 3. Lunar 9 ______. A. was launched eight years after Lunar 2 B. was launched with a human C. could send photographic data to Earth 4. According to the passage, which of the following is NOT true of Lunar 10? A. It was launched with a robot. B. It was launched in the same year with Lunar 9. C. It landed on the moon. 5. A fly by is a flight of a spacecraft ______ . A. near Venus, Mars and Mercury to take pictures B. made near a planet to gain data of the planet C. made in 1962, 1974 and 1898

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