McKnight Products is considering acquiring a manufacturing plant. The purchase price is $1,890,000. The owners believe the plant will generate net cash inflows of $315,000 annually. It will have to be replaced in nine years. To be profitable, the investment's payback period must occur before the investment's replacement date. Use the payback method to determine whether McKnight Products should purchase this plant. First enter the formula, then calculate the payback period. Payback period