Answer:
May 31 2017  Interest expense   720 Dr
             Interest Payable    720 Cr
Interest expense of 720 is accrued on May 31 2017.
Explanation:
The notes provides 8% interest rate which is the annual interest rate. The total interest on the one year note is 36000 * 0.08 = 2880 which is payable at the end of the term when the note payable is due. However, if the company prepares adjusting entry on a monthly basis or at the end of the period, it will record the interest expense that relates to that period and accrue it.
Till may 31 2017, 3 months have passes and the interest for 3 months is accrued which comes out to be 2880 * 3/12 = $720