问题如下：
Assume the following infomation of CC Inc.:
● current dividend: $4 per share
● current stock price: $45 per share
● the expected growth rate: 6%
● the flotation costs: 5%
The cost of external equity would be:
选项：
A. 15.42%.
B. 9.92%.
C. 15.92%.
解释：
C is correct.
The cost of external equity is:
$4(1+0.06) /$45(1-0.05)+0.06= 15.92%
没明白这里面flotation cost是什么？为什么要减去？股价里不应该还有费用啊？原理是什么？没明白
