【答案解析】①借款成本的计算:K=7%×(1-25%)=5.25%
②债券成本的计算:
NPV=14×9%×(P/A,K
d
,5)+14×(P/F,K
d
,5)-15
当K
d
=6%,NPV=14×9%×(P/A,6%,5)+14×(P/F,6%,5)-15=1.26×4.2124+14×0.7473-15=0.77(万元)
当K
d
=8%,NPV=14×9%×(P/A,8%,5)+14×(P/F,8%,5)-15=1.26×3.9927+14×0.6806-15=-0.44(万元)
K
d
=6%+

×(8%-6%)=7.27%
债券税后资本成本=7.27%×(1-25%)=5.45%
③普通股成本的计算:K
s
=

+8%=20%
④留存收益成本的计算:K
s
=
