Smart Corporation sells $600,000 of 12% bonds on June 1, 2015. The bonds pay interest on December 1 and June 1. The due date of the bonds is June 1, 2020. The bonds yield 10%, selling for $638,780. On October 1, 2016, Huawei buys back $300,000 worth of bonds for $315,000 (includes accrued interest). How much interest expense was paid on December 31. 2015?*