石膏模型使用应在石膏凝固干燥多长时间后开始()
A.10小时
B.12小时
C.18小时
D.22小时
E.24小时
参考答案:E
设计数据库的存储结构属于( )。
A) 需求分析 B) 概念设计C) 逻辑设计 D) 物理设计
What did the woman do [A] She drove her taxi into a car park. [B] She parked her car in a taxi park. [C] She waited for a taxi for too long.