Please Solve Part D only don't copy paste post in Operation Management

1. A retail has sixteen stores in a region supplied from eight supply sources. Trucks have a capacity of 20,000 units and cost $1,000 per load plus $200 per delivery. Thus, a truck making two deliveries charges $1,400. The cost of holding one unit in inventory at retail store for a year is $1.00. The vice president of supply chain is considering whether to use direct shipping from suppliers to retail stores or setting up milk runs (2 and 4 stores milk run) from suppliers to retail stores. D. Use Solver to determine the annual quantity level the VP should change their network from a 4 store milk run and to a 2 store milk run network. (At what quantity doe the total transportation and inventory costs of the two network strategies equal?)