Given a scientific question, generate a correct answer to it.

Example Input: Ultimately, the fluid that is lost from the blood vessels is returned through what system?
Example Output: lymphatic

Example Input: Nonshivering thermogenesis, which involves the breakdown of brown adipose tissue, is a special methods newborns have for what purpose?
Example Output: generating heat

Example Input: What is the unit used to measure voltage?
Example Output:
volts