15. An exporter of leather handbags has just entered a newmarket. This exporter faces the following relationship between the price of handbags and the demand for them:

p = 5 + 4800/D − 3000/D2, for D > 0 where p is the price per unit in dollars and D is the demand per month. The exporter wants to maximize his profit.

The fixed cost is $2,000 per month and the variable cost

(cv) is $35 per unit. (2.2)

a. What is the number of leather handbags that should be produced and sold each month, in order to maximize profit?

b. How do you know that your answer to Part (a)

maximizes profit?