producer is considering either producing and/or procuring certain part. The relevant data is as follows: Period 1 2 3 4 Production Capacity In-house 15 20 25 30 Outside Vendor 30 30 30 30 Unit Cost In-house 5 5 7 8 Outside Vendor 10 10 10 10 Demand 30 40 50 60 The initial inventory is 20 units and the holding cost is $2 per unit per period. Twenty units must be made available in inventory at the beginning of period 5. Use transportation algorithm to find the optimal aggregate plan.