题目内容

若非零向量b与n维向量组A：a1, a2, …, an中向量都正交，则向量组A必线性相关。

A. 对
B. 错

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Section B (This section includes 8 items, 4 points for each item, totaling 32 points.)Directions: In this section, you will hear two long conversations. At the end of each conversation, you will hear four questions. Both the conversation and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D). Then mark the corresponding letter on Answer Sheet 1 with a single line through the center.Conversation OneQuestions 8to 11 are based on the conversation you have just heard.8. A) They are discussing where to put the furniture.B) They are complaining about running out of hot water.C) They are planning to rent one of the rooms.D) They are talking about the condition of an apartment.9. A) Whether the rent is too high.B) Whether the rent covers water, electricity and gas.C) Whether there is a good supply of hot water.D) Whether there are too many people expecting to rent these rooms.10. A) $250.B) $500.C) $750.D) $1000.11. A) There scarcely are people wanting these rooms.B) They have a very nice talking.C) The man is child-free.D) The man offers the most reasonable rent.Conversation TwoQuestions 12 to 15 are based on the conversation you have just heard.12.A) He wrote on a seaside resort.B) He travelled with his family.C) He stayed at home to relax.D) He went shopping with the woman.13.A) She plans to have the man make a tour arrangement for her.B) She hopes that he could give her some advice on writing.C) She wants to get some suggestions about traveling.D) She complains to him about her boring holiday.14.A) Bring enough cash.B) Go with her mother.C) Resort to the man.D) Reserve a room.15.A) A busy city center convenient for shopping.B) A peaceful seashore with beautiful views.C) A huge bay with a littlebalcony.D) A room of standard sizethough noisy.