IRR of Startup Investment. You start$-$up a company and convince family members to invest a total of $$200,000,$ with the understanding that they will receive half of the proceeds when you sell the business or go public. $8$ years later your company is acquired by a larger company for a net price of $$1,200,000.$

What is the IRR of your family's investment?

a$.18\mathrm{.}9\%$

b$.16\mathrm{.}5\%$

c$.12\mathrm{.}6\%$

d$.14\mathrm{.}7\%$

e$.21\mathrm{.}0\%$