接地电阻应按( )技术条件选择参数。
A．频率
B．相对湿度
C．正常运行电流
D．中性点位移电压
参考答案：A,C,D
解析：[知识点] 接地电阻的选择
From the date________on the coin, we knew that it was made 500 years ago. [ ]
A. marking
B. marked
C. to be marked
D. having marked
鱼类性成熟年龄大体上可分为哪几种种类型？
