After careful analysis, Excellence Berhad has determined its optimal capital structure as shown in the following table. The cost of debt is estimated to be \7.2; the cost of preference share is estimated to be \13.5, the cost of retained earnings is estimated to be \16; and the cost of new ordinary share is estimated to be \18. All of these are after-tax rates. Excellence Berhad expects to have a significant amount of retained earnings available and does not intend to sell any new ordinary share. Calculate the WACC of Excellence Berhad