The State of Adaxen issued $$50$ million of perpetual bonds in $1990.$ The bonds were issued in $$100$ denominations with an annual coupon interest rate of $5\%.$ Determine the rate of return or current yield on these bonds if they are purchased at the current price of $$40.$

a$.12\mathrm{.}5\%$

b$.8\mathrm{.}0\%$

c$.5\mathrm{.}0\%$

d$.1\mathrm{.}25\%$

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