The part of the river that would have animals with very muscular bodies and adaptations that survive in turbulent water is the transition zone.
Population decreases by 15.
Birth rate means more population (positive), death rate means less population (negative), immigration means more (positive), and emigration means less (negative). So, just add and subtract the appropriate numbers:

Negative 15 people means that the population decreases by 15.
Answer:
The dna added on is to give the corn more strenghth
Explanation:
1. C) The soil will have no nutrients to grow the corn.
2. C) Crops may cause an increase of allergic reactions in humans
3. B) Decomposers