Computing interest expense. Gillette borrowed $250 million on October 1, Year 12. The debt carries an annual interest rate of 6 percent and is payable in two installments, on April 1 and October 1 of each year. The debt matures on October 1 , Year 32. Gillette's accounting period ends on December 31 of each year. Compute the amount of interest expense for Year 12 assuming that Gillette uses the accrual basis of accounting.