What effective interest rate will Frankie have to earn if his investments of $$2,000$ at the end of every three months for $20$ years are to have a maturity value in $20$ years of $$1,000,000?11\mathrm{.}56\%13\mathrm{.}81\%$ O $16\mathrm{.}19\%15\mathrm{.}29\%$O $17\mathrm{.}49\%$