A firm's production function is described by the isoquant map below. The wage rate is $4 and the rental rate of capital is $8.

a) Draw the firm's LR total cost curve. Label the points that correspond to points A, B and C in the figure and the coordinates of each point. (2 Marks)

b) Draw the firm's LR average cost curve. Label the points that correspond to points A, B and C in the figure and the coordinates of each point. (1 Mark)

c) What can you say about the existence of economies or diseconomies of scale in this industry? EXPLAIN. (2 Marks)