In 2010, the box industry was perfectly competitive. The lowest point on the long-run average cost curve of each of the identical box producers is $4, and this minimum point occurs at an output of 1,000 boxes per month. The market demand curve for boxes is

Q^D= 140,000 - 10,000 P,

where P is the price of a box (in dollars per box), and Q^Dis the quantity of boxes demanded per month. The market supply curve for boxes is

Q^S= 80,000 + 5,000 P,

where Q^Sis the quantity of boxes supplied per month.

a. What was the equilibrium price of a box? Is this the long-run equilibrium price?

b. How many firms are in this industry when it is in long-run equilibrium?