PL In business, variable costs are best defined as: O the amount of money spent over a given period of time. expenditures in PP&E such as factories and automation. O costs not tied directly to the cost of producing a unit such as administration, salespeople, and managers. O expenses that are tied to the sale of each unit of inventory (also known as Cost of Goods Sold) O costs and expenses of the company that fluctuate from year-to-year. None of the above