Treadmill, Inc., operates in a highly competitive industry, meaning it has limited capacity to increase prices. Sales are growing at a modest $3\%$ annually, and this trend is expected to continue. Treadmills suppliers have just announced a significant increase in the component parts used in its equipment. Treadmills management plans to achieve greater efficiencies in production, although it carried out a similar initiative just last year. In reviewing Treadmills projections, which cash flow driver will you consider to be a key part of your analysis?Accounts payable days.Operating expense percentage.Gross margin.