A factory manager is planning for the manufacture of plywood to be sold overseas. The fixed cost of operation is estimated at $800,000 per month while the variable cost is $155 per thousand board feet of plywood. The selling price will depend on how much will be produced and sold and is determined by the relationship, price per thousand board feet, p = $600 0.05D, where D is the amount produced and sold in thousands of board feet. Determine the range of profitable production. For profitable production, production must be at least 2500 thousands of board feet per month, but not more than (Round to the nearest unit.)