（1）total capital=5000000+1800000+15000000+4500000=26300000

The current yield on similar risk debentures in the
marketplace is 5.50% , the yield on preferred stock is 1*10%/1.6=6.25%, and the return on common stock is the return on equity 12%,

WACC=5.5%*(1-30%)*(5000000/26300000)+6.25%*1800000/26300000+12%*(15000000+4500000)/26300000=0.10057

（2）0.10057>4.25%

Since the required rate of return on capital is greater than the yield on federal bonds, WACC is suitable for investing in this project