When the price faced by a competitive firm was $5, the firm produced nothing in the short run. however, when the price rose to $10, the firm produced 100 tons of output. from this we can infer that the firm's total cost of producing 100 tons is less than $1000 the minimum value of the firm's average variable cost lies between $5 and $ 10 the firm's marginal cost of production never fall below $5 the firm's average cost of production was less than $10 the firm's marginal cost curve must be flat.