Hospitals are a better career choice
Three They are all pretty un-important to the rest of the story. Why didn't you just google this?
The preamble, i.e. the summary and main ideas of a text (in this case of the Declaration of Independence) is a brief introductory statement constituting its purposes and principles. Lucas said that this preamble can be applied to any government. And that the charges in the Declaration are exactly specific accusations against the king.