1.如下圖所示,已知負載 1:S =1000VA,PF =0.6(領前),負載 2:P=200 W,Q =300 VAR(滯後),負載 3:S =400 VA,PF = 1。求:總平均功率=【 (1) 】W,總視在功率=【 (2) 】VA