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$[$The following information applies to the questions displayed below.$]$

On January $1$ of this year, Olive Corporation issued bonds. Interest is payable once a year on December $31.$ The bonds

mature at the end of four years. Olive uses the effective$-$interest amortization method. The partially completed

amortization schedule below pertains to the bonds:

What was the annual market rate of interest on the date the bonds were issued?

Note: Enter your answer as a percentage rounded to $1$ decimal place $($i$.$e$.0\mathrm{.}123$ should be entered as $12\mathrm{.}3).$