Bethesda Hospital recently has developed an occupational medicine program. It wants to target employers in the Baltimore metropolitan area. The director of the program has a range of services within this program including toxicology assessment, education around issues such as preventing back injuries and stress management, and providing medical treatment at factories, should it be desired. Suggest three alternative ways the customer base for this new service could be segmented, and indicate how each base of segmentation would result in a change in the marketing mix.