Answer:
Researchers found that chronic exposure to a stress hormone causes modifications to DNA in the brains of mice, prompting changes in gene expression. The new finding provides clues into how chronic stress might affect human behavior.
because you know, i mean you know.
Answer: B
Explanation:
carbon monoxide is poison and can kill you
Air pollution. Cleaner burning than other fossil fuels, the combustion of natural gas<span> produces negligible amounts of sulfur, mercury, and particulates. Burning</span>natural gas does<span> produce nitrogen oxides (NOx), which are precursors to smog, but at lower levels than gasoline and diesel used for motor vehicles.</span>