Answer:
PCBs and DDT are chemicals that were banned more than 30 years ago, but our air, water, land, and bodies are so contaminated that decades of cleanup efforts have yet to eliminate their threats to our health. Today, food is one of the most likely exposure routes to PCBs.
Answer:
An event can cause changes to occur in one or more of the spheres, and/or an event can be the effect of changes in one or more of Earth's four spheres. This two-way cause and effect relationship between an event and a sphere is called an interaction. Interactions also occur among the spheres.
Answer:
R (capital letter) is the dominant allele so the phenotype is the same
Explanation:
Evolution can be defined as the process of changes in the genetic pool of a population over time. The process of natural selection operates the evolution of any population. Evolution acts upon a whole population instead upon on single individual. A single individual doesn't evolve, instead ratios of the genetic types within a population changes when it is evolving, and eventually, complete evolution occurs.
Hence, the given answer is 'true'.