Let us look at the what, why and how of studying extreme places like the deep earth and the deep space. Scientists need to figure out as to 'what' they want to look at such places, be it a new exotic creature or bio-genesis (birth of life). Unless there are several testable hypothesis constructed, such a study cannot begin. The 'why' aspect deals with the purpose of such research and expeditions. Is it of any use to the humans, or will it improve our current understanding of a phenomenon? The 'how' aspect deals with the technology and the economic assistance that can help in undertaking such a research. All these are the challenges that needed to be thoroughly considered to make such a research or expedition possible.
Heat is generated by friction is one of the ways and fuel and air if making flames
Answer:
Estrogen levels days prior to ovulation
Explanation:
Estrogen is responsible for the reproductive system in women and high levels occur naturally during menstruation as compared to glucose levels in blood as the pancreas is constantly producing more insulin to lower the glucose in blood.