Time left 2:39:33 The long run average cost of a purely competitive firm at the level 10 of output is 20, that is, AC(10)=20. For the same firm, the average cost at 15 is 15, that is, AC(15)=15. Does the production function of this firm have the property of decreasing returns to scale? a. Not enough information to answer question. O b. Yes O. c. No