EDTA与金属离子形成的络合物的特点()。
A.络合面广
B.络合比简单
C.络合物的水溶性大
D.络合反应速度快
E.有比较简单的确定终点的方法
参考答案:A, B, C, D, E
必须具有对话功能,引用历史数据功能,引用知识库功能的系统是()。
A.决策支持系统
B.电子数据交换系统
C.电子订货系统
D.网络加值系统
Playing a major role in the economic life of the United States, ______.
A. women currently make up 46 percent of the work forceB. currently women make up 46 percent of the work forceC. the work force is currently made up of 46 percent womenD. 46 percent of the work force is currently made up of women