In a large microelectronics plant, the assembly cell for circuit boards has a demand for 200 units an hour. Two feeder cells supply parts A and B to the assembly cell (one A and one B for each board). Standard containers that look like divided trays are used. A container will hold 20 As or 10 Bs. It takes 10 minutes to fill up a container with As and 20 minutes to fill up a container with Bs. Transit time to the assembly cell is 5 minutes for both A and B. No safety factor is used. Set up a kanban control system for the assembly process.