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问题 填空题

已知球内接正方体的表面积为6，则球的表面积等于               .

答案

本题考查球的性质.

正方体内接于球，则此正方体的对角线长恰好为其外接球的直径.

设正方体的棱长为，由正方体的表面积为6，则，解得；

所以此正方体的对角线长为；

于是其半径为，所以此球的表面积为，则球的表面积为

 

问答题

Mr Liu entered into an agreement to buy a second-hand car from Mr Feng at a price of RMB 50,000 yuan. After the conclusion of the agreement, Mr Liu paid the price and Feng delivered the car to Mr Liu. The two parties, however, did not register the sale of the car. Following the sale Mr Liu took the car to a repair shop to repair the air conditioner. After the completion of the repair and on the way home, a fire accident occurred due to the defect of the air conditioner and caused serious damage to the car. Mr Liu returned to the repair shop claiming compensation for the defect of the air conditioner. The repair shop insisted that it was not liable for the fire accident and the resulting damage to the car. In addition, after retrieval of the data from the local vehicles registration centre, the repair shop found that the registered owner of the car was still Mr Feng, not Mr Liu. Under such a situation it refused to discuss the dispute any more with Mr Liu, on the ground that he was not a legitimate owner of the car. When Mr Liu asked Mr Feng to negotiate with the repair shop, Mr Feng was reluctant to do so on the ground that the transaction between them was over since he had duly delivered the car to Mr Liu. Required: Answer the following questions in accordance with the relevant provisions of the Property Law, and give your reasons for your answer:

(c) state whether the repair shop should be liable for the damaged car if the fire was caused by the defect of the air conditioner. (2 marks)
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单项选择题

女性，29岁，左下后牙床肿痛伴左下颌角区肿胀4天。检查：体温38.4度，开口度一指半，垂直低位阻生，牙龈充血，挤压有少量脓液溢出，以左下颌角为中心肿胀，充血、压痛明显

此患者最可能的诊断为（）。

A．急性智齿冠周炎

B．左嚼肌间隙感染

C．左颌下间隙感染

D．左下颌骨边缘性骨髓炎

E．左嚼肌区放线菌病
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