4. Is there one final source of authority, or is it broken up in a few different
places?

Broken up into a few different places

Explanation:

When the Founding Fathers drafted the Constitution, they did it in such a way that power would not be centralized one one source. The United States Federal Government is broken up in three branches, each with its own powers as well as powers to limit the powers of the other branches if those branches overstep.

This is called the principle of ''Separation of Powers''. The branches that the US Government is divided into are;

These three branches as earlier mentioned, have powers vested in them that allow them to do certain things that the other branches can not. At the most basic level, the Legislative makes laws, the Executive enforces them and the Judiciary administers them.

Duties of the Executive include but are not limited to;

Duties of the Legislative;

Duties of the Judiciary;

A typical example of the Separation of Powers is this; Congress can pass laws but they are only enforceable after the President signs off on them. If the Judiciary however finds that the law is Unconstitutional, it can strike it down and send it back to Congress.  

after defeating german forces in north africa allied leaders turned their attention to "italy," since this was the location that made the most geographic sense before invading northern europe via france.