How do I do this question?

On December 31, 2015, Tran Co. performed environmental consulting services for Hayden Co. Hayden was short of cash, and Tran Co. agreed to accept a $100,000 zero-interest-bearing note due December 31, 2017, as payment in full. Hayden is somewhat of a credit risk and typically borrows funds at a rate of 15%. Tran is much more creditworthy and has various lines of credit at 8%. (a) Prepare the journal entry to record the transaction of December 31, 2015, for Tran Co. (b) Assuming Tran Co.'s fiscal year-end is December 31, prepare the journal entry for December 31, 2016. (c) Assuming Tran Co.'s fiscal year-end is December 31, prepare the journal entry for December 31, 2017