Find the interest due on each of the notes, using the interest formula method. (Use 360 days a year.) Interest 1. A $23,000 note at 8 percent for 180 days, issued February 15. 2. A $6,300 note at 12 percent for 3 months, issued October 3. 3. A $28,000 note at 9 percent for 180 days, issued October 18.