TB Yoga used its weighted average cost of capital as the discount rate for the project. The company has a debt-to-equity of ratio 50%, and observed that a competitor has a debt-to-equity ratio of 1/3 (i.e. 33.33%) and a cost of equity of 13%. The current corporate bond rate is 8%, while the corporation tax rate is 25%.

请问怎么计算TB Yoga的WACC，谢谢各位大神。。。。
我的计算，蒙的，re2是 competitor的 cost of equity，re是TB公司的，r0是无负债下的WACC

re2 =r0 + (r0-rd)(1-T)*D/E

13%= r0 + (r0-8%)(1-25%)*1/3

r0=12%

re =r0 + (r0-rd)(1-T)*D/E =12%+(12%-8%)(1-25%)*1/2=13.5%

WACC=E/(D+E)* re+ D/(D+E)* rd *(1-Tax rate)

=2/3*13.5%+1/3*8%*(1-25%)=11%