A taxable corporate bond currently yields at $8\mathrm{.}7\%$ and a municipal bond of similar maturity and risk is yielding $6\mathrm{.}2\%.$ What is the break even rate at which an investor would be indifferent between the two?

A$.26\mathrm{.}49\%$

B$.33\mathrm{.}12\%$

C$.24\mathrm{.}33\%$

D$.28\mathrm{.}74\%$

E$.30\mathrm{.}28\%$