第13题: [单项选择]慢性汞中毒治疗首选药物是 A. 依地酸二钠钙 B. β-巯乙胺 C. 二巯基丙磺酸钠 D. 青霉胺 E. 美蓝 参考答案:C
第14题: [单项选择]She has proved that she can be relied on in a crisis. A. lived on B. depended on C. lived off D. believed in 参考答案:B 答案解析:[解析] rely on：依靠。depend on:依靠；依赖。The town depends almost solely on the tourist trade. 小镇的经济主要依靠旅游业。li
第21题: [单项选择]描述概念模型的常用方法是( )。 A. 建立数据模型方法 B. 需求分析方法 C. 实体-联系方法 D. 二维表方法 参考答案:C 答案解析:[解析] 描述概念模型的常用方法是实体-联系方法。
相关知识点：
数据模型是描述数据、数据联系、数据操作、数据语义以及一致性约束概念工具的集合。数据模型可分为概念模型、结构模型。实体联系模型是
第24题: [单项选择]Questions 11 to 18 are based on the conversation you have just heard. A. He decided not to Cancel his appointment. B. His new glasses aren’t comfortable. C. He’s too busy to get a checkup. D. He has to check when the appointment is. 参考答案:C 答案解析:[听力原文] W: When are you going to have your eyes checked M: I had to cancel my appointment. I c
