6. Longrun cost relationships The following graph shows the shortrun average total cost curves and the longrun average total cost curve for a publishing rm. The ve marked quanties indicate points of tangency.r between each shortrun average total cost curve [1411'le and the longrun average total cost curve (LEM: for example. Q1 marks the point of tangencv between AIIUI and LRAITC. The orange point on ALTO; indicates the rm's current output level in the short run (Q4).