直流输电系统的损耗包括（）。
A.变压器损耗
B.平波电抗器损耗
C.直流滤波器损耗
D.直流线路损耗
参考答案：A, B, C, D
根据句意补全下列句子。
1. It is very cool in .
2. I put on my shorts and T-shirt in .
3. It is rainy in .
4. There is ice and snow in .
5. Today is cold, please your coat.
6. I like to on the ice. She likes to on the .
通信障碍是怎样进行分类的？
