2) Solve the following case and report the optimal total annual cost (minimum total annual cost): A local 7/11 sells Old Dutch snack packs. Packs cost $1.80 each, and 7/11 sells them for $3.25 per pack. Each snack pack has a shelf life of 12 months. 7/11's average sales are 40 per week. The annual inventory holding cost rate is 20% of the cost, and it costs the shop $2.00 to place an order with Old Dutch If Old Dutch offers a 5% discount on orders of 800 or more, a 10% discount for 1600 or more, and a 15% discount for 2100 or more, determine 7/11's optimal order quantity. (8 marks) To get the credit for this question, you must show all the steps and all of the calculations