Z-Mart uses the perpetual inventory system and has its own credit card. Z-Mart charges a per-month interest fee for any unpaid balance on its store credit card at each month-end.

Apr.		30		Z-Mart sold merchandise for $2,100 (that had cost $1,200) and accepted the customers Z-Mart store credit card.
May		31		Z-Mart recorded $3 of interest earned from its store credit card as of this month-end.

Prepare journal entries to record the above credit card transactions of Z-Mart.