11a+9=4a+30
11a-4a=30-9
7a=21
a=3
Answer:
Evolution
Explanation:
Natural selection is usually defined as a process by which an organism or a specific type of living species adapts to a new environment in order to grow, develop, reproduce and protect themselves from the predators. During this time of migration, evolutionary changes occur in organisms over a specific period of time. It occurs naturally and there are several factors that affect these changes occurring in an organism.
Evolution simply refers to the growth, development, and expansion of an organism that occurs over a definite time period.
Answer:
Mixtures occur when two or more materials are combined and each material keeps its own properties. All of the following are mixtures EXCEPT
Chocolate milk
Explanation:
Chocolate is a mixture but it does not keep its original properties
Volcanic eruption. a solidified lava flow will devoid plants of necessary soils in which to grow.