Janis has demand for 40,000 desks p.a. and the purchase price of each desk is $25. There are

ordering costs of $20 for each order placed. Inventory holding costs amount to 10% p.a. of

inventory value.

Calculate the inventory costs p.a. for the following order quantities, and plot them on a

graph:

(a) 500 units

(b) 750 units

(c) 1,000 units

(d) 1,250 units