Consider the following total revenue (TR) and total cost (TC) relations where Q denotes output:

TR = 1800Q + 0.006Q²

TC = 12 100 000 + 800 Q + 0.004 Q²

(a) Calculate output, marginal cost, average cost, price and profit at the average-cost minimizing level of output.

(b) Calculate output, marginal cost, average cost, price and profit at the profit-maximizing level of output.

(c) Compare and discuss your answers to parts (a) and (b).