第28题: [单项选择]香豆素基本母核是() A. 苯骈α-吡喃酮 B. 苯骈α-呋喃酮 C. 苯骈α-吡咯酮 D. 苯骈β-呋喃酮 E. 苯骈γ-吡喃酮 参考答案:A 答案解析:香豆素基本母核是苯骈α-吡喃酮,所以答案为A。
第29题: [单项选择]{{B}}Passage One
Questions 26 to 28 are based on the passage you have just heard.{{/B}} A. Far away from the city. B. Inside tile city. C. Near the city. D. In the city center. 参考答案:A 答案解析:[听力原文]26-28
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