Which document would be considered the "birth
certificate" of the USA?

In my opinion I'd say The Declaration of Independence.

The Declaration of Independence expresses the ideals on which the United States was founded and the reasons for separation from Great Britain.

Explanation:

Hope it helps!

the virginia plan called for three branches of government and two houses of congress. representation in each house would be determined by population. the new jersey plan called for three branches of government and a single house of congress. each state would have an equal vote.

in the 1950s, country music came into its own before rock-n-roll took off in the 60s while jazz and classical music continued to innovate