Use the figure below to answer the following question. Price Quantity demanded (dollars per box) (thousands of boxes per week) 7.3 1000 10.4 900 13.6 800 16.8 700 20 600 23.2 500 Quantity Marginal cost Average Average (boxes per (dollars per |variable cost total cost week) additional (dollars per (dollars per box) box) box) 400 12.8 15.6 25.6 500 14 14 22 600 15.3 14.2 20.86 700 16.8 14.4 20.12 800 20 15 20 900 24.8 16 20.44 1000 41.4 18 22500 14 14 22 600 15.3 14.2 20.86 700 16.8 14.4 20.12 800 20 15 20 900 24.8 16 20.44 1000 41.4 18 22 The top table shows the market demand schedule for paper. The market is perfectly competitive and there are 1,000 firms that produce paper. Each firm has the costs shown in the bottom table when it uses its least-cost plant. The market price in the long run is a box and the equilibrium quantity produced in the long run is boxes a week. O $20.00; 300,000 $8.40: 350,000 $20.00; 600,000