I$)$ Calculate the weighted average cost of capital for Microsoft Corporation under the following assumptions. $(10$ points$)$

a$)$ U$.$S$.10$ year t$-$bond yield $=4\mathrm{.}3\%$

b$)$ Market Risk Premium $=6\%$

c$)$ Tax Rate $=21\%$

d$)$ Rating of debt $=$ AAA

e$)$ Default Risk Premium $=70$ basis points

f$)$ Market Cap. $=3\mathrm{.}32$ trillion dollars

g$)$ Total Debt $=$$$106$ billion

h$)$ Beta $=0\mathrm{.}85$