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;
-PET scan
A PET scan uses radioactive markers in the blood to monitor blood flow and metabolic activity via x-ray
Explanation;
-A positron emission tomography (PET) scan is an imaging test that helps reveal how the tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity. This scan can sometimes detect disease before it shows up on other imaging tests.
-A PET scan is used to diagnose certain health conditions, to plan treatment, to find out how an existing condition is developing, and to see how effective a treatment is.
-In a PET scan, a machine detects radiation that is emitted by a radiotracer. A radiotracer consists of radioactive material that is tagged to a natural chemical, such as glucose.
With regards to gender differences in coping strategies, male is to female as fight or flight is to TEND AND BEFRIEND. Men and women have different strategies in coping with stress; men usually exhibit the fight or flight tendency while women exhibit the tend and befriend tendency.
Endogenous processes - Under surface of the earth.
Exogenous processes - Above the surface of the earth.
Lithosphere - Is broken into tectonic plates.
Plates - made of thick slabs of rock, compose the crust/ocean crust .
7 major plates - Pacific, North America, South America, Eurasian, Antarctic, indo-Australian
Answer:
Hypothesis If the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.
Explanation:
