The shipping depаrtment аt а lоcal manufacturer оf glass cоffee mugs follows the two-step process shown below to get each coffee mug ready for shipping. Before each batch of mugs, the "wrap in bubble wrap" station has a changeover time of 60 seconds. With a batch size of 300 coffee mugs, what will be the maximum inventory between the "bubble wrap" and "box" work stations? Assume that demand is unlimited.