_____(large ; small) relative to the output of a single producer. A perfectly competitive firm faces an ____ (elastic ; inelastic) demand. The change in total revenue that results from a one-unit increase in the quantity sold is marginal____ (cost; price; revenue). When a perfectly competitive firm maximizes profit, marginal revenue equals ____ (average variable; marginal ) cost. When a firm shuts down, it incurs a loss equal to its total ____ (variable; fixed ) cost. A firm will shut down if price is less than