The table below shows a firm's capital structure and estimated capital costs. Calculate this firm's weighted average cost of capital.
Source of capital Amount After Tax Cost of Capital
Bonds $1,250,000 5.25%
Preferred Stock 500,000 12.80%
Retained Earnings 3,800,000 15.35%
A. 9.00%
B. 10.51%
C. 12.85%
D. 15.35%