<span>A typical major requirement for a business major would be a course in C. economics.
Since they are going to deal with money and numbers a lot, it is only sensible to take a course in economics.
Physical education, physics, and music theory have nothing to do with business.
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I believe the answer is: They thought it was animals.
At that time, the colonists still haven't been familiar with the local tribes in that area. By the time they realized that that the sound came from the native (as some sort of war cry that they do to initiate an attack) , it's far too late for them to run away.
The goods would get to the destination faster.