How high is the periodic monthly payment at an annual interest rate of 8.75% over a period of 3 years? The cash value is 5,000 currency units and is always paid at the beginning of a period. The future value is 8,000 currency units.
如果一项贷款的现值是 5,000 个货币单位，未来值是 8,000 个货币单位，年利率为 8.75%，偿还期限为 3 年，且始终在周期的开始时支付，则定期的月支付额是多少？