答案：(1)股利折现模型：普通股资本成本=0.8/[8X (1 -6%)]X 100% + 2% = 12.64%(2)资本资产定价模型：普通股资本成本=8% + 1. 2 X (12% - 8%) = 12.8%(3)无风险利率加风险溢价法：普通股资本成本=无风险利率+风险溢价=8％+4％=12％
解析：(1)股利折现模型：普通股资本成本=0.8/[8X (1 -6%)]X 100% + 2% = 12.64%(2)资本资产定价模型：普通股资本成本=8% + 1. 2 X (12% - 8%) = 12.8%(3)无风险利率加风险溢价法：普通股资本成本=无风险利率+风险溢价=8％+4％=12％