How can carbon cycle very quickly back into the enviornment

The short term cycling of carbon begins with carbon dioxide (CO2) in the atmosphere. Through photosynthesis, the inorganic carbon in carbon dioxide plus water and energy from sunlight is transformed into organic carbon (food) with oxygen given off as a waste product.

Explanation:

Physical change -

It refers to any change during any process , where there is no new substance is formed , is referred to as a physical change.

Any change in the state of matter is characterised under physical change.

Chemical change -  

It refers to any change in a chemical process , where there is formation of any new substance , is referred to as a chemical change .

From the options given in the question,

1. Apple turning brown , on air exposure , is an example of chemical change .

2. The physical state of mercury is liquid ,  is an example of physical change .

3. phosphorus burns on exposed to air , is an example of chemical change .

4. The gas Neon is colorless at the room temperature , is  is an example of physical change .