1. The problem statement, all variables and given/known data http://img42.imageshack.us/img42/3537/powersyst.jpg [Broken] 2. Relevant equations P = I^2 R 3. The attempt at a solution Here's what I have so far: I1 = 49.68A<-68.6 degrees (top loop) I2 = 49.68A<-128.6 degrees (bottom loop) I3 = 28.68<-98.6 degrees (triangle loop) a) PA12 = (49.68A)^2(12) = 29,617.23 W PB12 = (49.68A-49.68A)^2(12) = 0 W PC12 = (49.68A)^2(12) = 29,617.23 W Ptotal12 = 29,617.23W + 0W + 29,617.23W = [59,234 W] answer b) Pab400 = (49.68A-28.68A)^2(400) = 176,400 W Pbc400 = (49.68A-28.68A)^2(400) = 176,400 W Pca400 = (28.68A)^2(400) = 329,017 W Ptotal400 = 176,400W + 176,400W + 329,017W = [681,817 W] answer Now c) and d) I am unsure of. I was thinking power factor would be 59,234 W/681,817W which would give me a p.f. of 0.087 but that doesn't seem right, and efficiency I have no clue how to calculate. I'm not 100% sure I even did parts a) and b) right. Any help/explanations would be greatly appreciated!!