If sales are $250,000, merchandise purchases are $130,000, and the balance of the merchandise inventory account decreased by $20,000 during the period, then the cost of goods sold must be:g statements is false when considering cost behavior within the relevant range? multiple choice a variable cost remains constant, in total, as the activity level changes. a variable cost is constant if expressed on a per unit basis. a fixed cost remains constant, in total, regardless of changes in the level of activity. the average fixed cost per unit varies inversely with changes in the level of activity