the answer is a because if the model is based on experimental data it wont be good unless it has been tested.
Answer:
The Nitrogen Returns into the Soil (Nitrogen Cycle)
Explanation:
After a plant dies it's the job of a decomposer to carry along the nitrogen back to the surface so that it may continue to cycle along, until it eventually returns back to the decomposer through the death of another plant. This part of the cycle is small compared to the whole Nitrogen cycle.
Explanation:
the width would be 216 x 279mm
