单相短路时的复合序网是在短路点处是如何连接的？
参考答案：
正序、负序和零序三个序网串联。
The bread my wife makes is much better than ____ you can buy at a store. [ ]
A. that which
B. one that
C. that of which
D. this of which
缓存(Cache)存在于______。
A．内存内部
B．内存和硬盘之间
C．硬盘内部
D．CPU内部
