The current spot exchange rate is $S^{\frac{}{\text{\$}}}=\frac{106\mathrm{.}24}{\text{\$}}$ and the $1-$year forward rate is $F^{\frac{}{\text{\$}}}=\frac{108\mathrm{.}45}{\text{\$}}.$ The interest rate in the U$.$S$.$ is $2\mathrm{.}5\%.$

a$.$ What should the Japanese interest rate be$?$

b$.$ What is the forward premium or discount?