Please help me answer this. My original answer from my tutor was 12.09 and that was wrong and the answer I just got on my own was wrong of 2.05. Please walk me through this problem.

HAHADA EQ LIATION Situational Software Co. (SSC) is trying to establish its optimal capital structure. Its current capital structure consists of 20% debt and 80% equity; however, the CED believes that the rm should use more debt. The risk-free rate, FM, is 6%; the market risk premium, RPM, is 5%; and the rm's tax rate is 40%. Currently, SSC's cost of equity is 13%, which is determined by the CAPM. What would be SSC's estimated cost of equity if it changed its capital structure be 50% debt and 50% equity? Round your answer to two decimal places. Do not round intermediate steps. "all