Suppose that the current one$-$year Treasury bill rate is $3\mathrm{.}15$ percent and the expected one$-$year rate $12$ months from now is $4\mathrm{.}25$ percent. According to the unbiased expectations theory, what should be the current rate for a two$-$year Treasury security?

Multiple Choice

$3\mathrm{.}70\%$

$4\mathrm{.}15\%$

$2\mathrm{.}36\%$

$4\mathrm{.}74\%$