20. The answer is 1 (Precambrian)
21. The answer is 4 (Pennsylvanian)
22. The answer is 2 (Bony Fishes, Dinosaurs, and Mammals)
23. The answer is 2 (Reptiles)
Answer:
e.DDT
Explanation:
DDT is biologically magnified and concentrated as it moves through the food web. This increase in concentration is due to Metabolism of DDT which excretes more slowly than the nutrients which moves from one trophic level to next. so DDT accumulates in the body especially in the Fats.
a chemical element or substance required in trace amounts for the normal growth and development of living organisms.
Genetic drift is the dramatic almost sped up process of natural selection due to the untouched habitat the species I lives in. Genetic drift is characterized by the changing in alleles, whether more or less, natural selection could care less as long as they're creating diverse populations.
