Associates issued $600,000 par value, 10-year bonds on January 1, 2018, with a 2% stated interest rate. It will make interest payments semiannually each June 30 and December 31 with the first interest payment at the end of the period on June 30, 2018. The market rate of interest on the date of the bond issue was 4%. On what dale do the bonds mature? Prepare the journal entry when the bonds mature (you do not need to include an entry for the interest payment).