Four existing assembly lines have the flexibility to handle two products, but a huge jump in budgeted demand requires adding additional lines. Operations are scheduled for 350 days/year with two shifts of 10 hours each per day. In order to ensure they can react to rush or large orders, a 12% capacity cushion is desired. How many additional assembly lines are needed to deal with the following forecast: Model A Model B Annual Demand 40,000 60,000 Set-up Time/ Batch 4 hrs 6 hrs Run Time per unit 1 hr 30 min Batch Size 2,000 3,000.