Advertising is a activity. supply of replacement parts is a activity. support; primary primary; primary support; secondary primary; support

Michael Porter  defined the primaty activities in his value chain.
Advertising is a primary activity. Supply of replacement parts is a primary activity. support; primary primary; primary support; secondary primary; support. These activities are used to provide a company with a competitive advantage in any one of the five activities so it has an advantage in the industry in which it operates and include logistics, operations, outbound logistics, marketing and sales, and service.

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.