Kathleen Pierce began a new business this month. She received a report from an outside firm specializing in physical inventory counts that the ending inventory was $1,426.60. However, according to Kathleen's records, the inventory at month end was $1,517.50. Kathleen has rechecked the records several times and still comes up with the same amount. The company had no inventory at the beginning of the month and 70 units on hand per physical inventory count at the end of the month. The company uses the periodic method. Listed below are the company's purchases for the month: Purchase Units Unit Cost 1 40 $20.00 234567 50 21.00 60 20.50 75 20.00 90 19.00 50 22.00 45 21.50 Required: 1. Write an explanation for Kathleen on how the difference in amounts could occur. (Hint: use different cost formulas to calculate the ending inventory). Provide numerical support.