Why do preferred routes (IFR, terminal, etc.) exist and what purpose do they serve?

Overview
Why do preferred routes (IFR, terminal, etc.) exist and what purpose do they serve?
Instructions
Complete this assignment by posting an initial response by Thursday. You may use a textual response or Kaltura Capture. If you use Kaltura Capture your video should be a minimum of 3-5 minutes. Use credible internet sources to research preferred routes. All submissions must be original and unique unless you are citing a direct quote. In-text citing and references in APA format are required for this assignment. See below for information on APA requirements.
Complete this assignment by doing the following:
Use credible internet sources for your research.
Post a three-paragraph response which includes:
An introduction paragraph that summarizes preferred routes.
A paragraph or two explaining your understanding of why the FAA created preferred routes.
A conclusion paragraph that summarizes the purpose of preferred routes.
References
At least three references are required for your initial post.

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