There are many reasons to why slaves were essential in the colonial economy:
Slaves were generally used more in the south, because large plantations were found there, which meant that the need for large amounts of workers.
Slaves provided cheap labors, and as they were not "citizens" of the US, they were not allowed their rights.
Slaves were also relatively easy to buy and replace, however, their survival rates were not that good after they traveled long distance.
etc.
hope this helps
Symptoms of severe anxiety evident in this case include; confusion, sweating, withdrawal, rapid speech, and a perceptual field that is reduced greatly and distorted. The perceptual field is heightened in mild anxiety while in moderate anxiety, the ability to think clearly is hampered but learning and problem solving can still take place. Additionally in panic, communication is unintelligible or there is an inability to speak.
They go to the brain then sent out to the rest of your body