Conversation so far:
is the us postal service private or government
The United States Postal Service is an independent agency of the executive branch of the United States federal government.
what is the usps agency responsible for
The USPS is responsible for providing postal service in the United States, including its insular areas and associated states.
where does the usps agency get authority
The USPS is one of the few government agencies explicitly authorized by the United States Constitution.
how many employees does the usps have
The USPS has 644,124 employees (503,103 career, 141,021 non-career) as of 2017.

Question: where is the headquarters
Self-contained rewrite: where is the headquarters of the usps