It may be determination (not sure though)
Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population. If they are met, natural selection automatically results.
A dam is a structure built across a stream or river to hold water back. Dams can be used to store water, control flooding, and generate electricity.
Answer:
D.20,000
Explanation:
The Gross Annual Primary Productivity for the wetland ecosystem is the amount of carbon taken up by the aquatic producers through photosynthesis.
Given that: Net Annual Primary Producer is 8,000 kcal/m2 per year, and respiration by the aquatic producers is 12,000 kcal/m2 per year, using the formula NPP = GPP – Respiration, we can determine the Gross Annual Primary Productivity of the wetland ecosystem.
NNP = 8,000 kcal/m2
Respiration = 12,000 kcal/m2
GPP = x
8,000 = x – 12,000 (NPP = GPP – Respiration)
Solve for x:
x = 8,000 + 12,000
x = 20,000 kcal/m2 per year
GPP = 20,000 kcal/m2 per year