Answer:
<h2>C. To date rock layers</h2>
Explanation:
<em>They can help determine the relative age of rock layers</em>.
Microorganisms that are involved in the nitrogen cycle are able to break the triple of elemental nitrogen using special enzymes that they have developed and make ammonium. Other organisms like plants are unable to break the triple bond and therefore rely on these microorganisms so that they can absorb the ammonia
The answer is that infant circumcision is not ethically necessary. The reason to this is that there are no proof of evidence as to why it is ethically necessary for it to be done to an infant. It is also because other medical professionals thinks that doing circumcision in an infant will create issues in terms of their health, producing complications. That is why it is not ethically necessary for it to be done on an infant.
Answer:
Humans have a heart with two atria and two ventricles that pushes blood in one direction. Some animals have hearts similar to humans but, other animals have only one atrium and one ventricle or a cardiovascular system that can push blood in two directions.