Suppose the market for good X is competitive. Assume there are 1000 firms in this market and all these firms are identical. The following table provides the market demand and supply for good X (in thousand units). Suppose the firm's objective is to maximize profit and its average total cost for producing the profit-maximizing quantity is $30. Use table 1. attached to answer the following questions:

a)Determine and describe the firm's equilibrium quantity and profit. Can this firm continue to make the profit in the long run? Explain (30 marks)

b)Assume a firm, in the long run, produces 400 units and the firm's minimum average total cost is $20. What is the new market equilibrium price and quantity and how many new firms have entered the market? Assume the new firms and existing firms are identical. (30 marks)

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Table 1: Market demand and supply for good X at the given price. Price per unit Quantity demanded Quantity supplied (in thousand units) (in thousand units) 0 1000 0 10 900 100 20 800 200 30 700 300 40 600 400 50 500 500 60 400 600 70 300 700 80 200 800 90 100 900 100 0 1000