1 Total revenue of all National Football League teams from 2001 to 2015 (in billion U.S. dollars)*Total revenue of the National Football League 2001-2015. 2  National Football League average franchise value from 2000 to 2016 (in million U.S. dollars)National Football League - average franchise value 2000-2016.
There are two types of systems in organizations: closed systems and open systems. An open system interacts with its environment through giving and receiving information. Closed systems are closed off from the outside environment, and all interaction and knowledge is transmitted within the closed system only.
More in High Blood Pressure. The circulatory system, also known as the cardiovascular system, is a simple loop which starts, and ends, with your heart. It is a closed system, meaning blood does not enter or leave the system during its journey from your heart to your body and back again. In such a system, a continuous flow of the same liquid can be pumped through the loop again and again.