3% of the Earth's water is freshwater.<span />
Scientists developed the time scale by studying rock layers and fossils world wide.
Radioactive dating helped determine the absolute divisions in the time scale. so mass extinction help because there is more to study
Answer: Burns
Explanation: <u>Dehydration</u> of as little as 2% of total body water can result in a significant impairment. For example: <u>Hormonal changes that affect fluid and electrolyte homeostasis.</u>