A closed system is a system that makes no physical or chemical exchanges with its environment. Of these systems provided as choices (tree, human, clock, car), only a clock does not make exchanges with the environment, except for energy.
Therefore, of that list, only a clock would be a closed system.
Hope that helped! =)
Answer:
1. Bureau of Land Management
2. US Fish and Wildlife Service
3.US Forest Service
4. Bureau of Land Management
5.National Park Service
Explanation:
Answer: Option C) Pluto
Explanation:
Pluto is described as a dirty ice ball of frozen gases and rocky material. It was the ninth planet to be discovered.
