题目

by her classmates for fatness, she decided to go on a diet so as to lose weight. A . To be annoyed B . To have been annoyed C . Having been annoyed D . Having annoyed 答案：C烧红的铁制工件投入一定质量的凉水中温度迅速下降，该过程中（　　）A．工件内分子平均动能一直在减小B．工件内分子间的分子势能保持不变C．工件内所有分子动能和分子势能将同时减少D．工件内能一定减小且减小量等于水的内能增加量（不计水周围的能耗）