The answer is the sympathetic nervous system. This regulates
the reactions of the body to an acknowledged threat and is accountable for the
"fight or flight" reaction. Over time, this over-stimulation of the
SNS can go to clear-cut marks of imbalance like: anxiety, shallow breathing,
augmented heart rate, poor quality sleep, restlessness, night
sweats, increased agitation/irritability, fatigue, and
nervousness just to name a few.
By trading, companies/people can buy cheap items that can be sold for much more, bringing them profit.
B. designs cities is the best answer