5. 如下圖電路, I1 以及整個電路總共消耗的實功率為何? (A) I1 = 20∠53.1° A,P = 4500W(B)I1 = 20∠-53.1° A,P = 2000W(C)I1= 20∠-53.1° A,P = 4500W(D) I1= 20∠-53.1° A,P = 6500W