ools 10. Long-run cost relationships The following graph shows the short-run average total cost curves and the long-run average total cost curve for a publishing firm. The five marked quantities indicate points of tangency between each short-run average total cost curve (SRATC) and the long-run average total cost curve (LRATC); for example, Q marks the point of tangency between SRATC, and LRATC The orange point on SRATC indicates the firm's current output level in the short run (Q4). COST PER UNIT SRATC, SRATC SRATC LRATO SRATC, SRATC OUTPUT ?