Two years ago, you invested $$3,450.$ Today, it is worth $$4,200.$ What rate of interest did you earn?

Multiple Choice

$\mathrm{.}86\%$

$10\mathrm{.}34\%$

$5\mathrm{.}60\%$

$4\mathrm{.}60\%$

$5\mathrm{.}17\%$