Where do I FedEx my passport application to be certain it arrives at correct location?

Question: We need a physical address for the application and I am requesting a signature receipt to make sure the passport arrives safely. Where do I mail

Source: http://www.us-passport-service-guide.com/where-do-i-fedex-my-passport-application-to-be-certain-it-arrives-at-correct-location.html

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