The President of the United States
The President of the United States is the head of the executive branch. The President gets help from the Vice President, department heads (called Cabinet members), and heads of independent agencies.
A monarchy or one that has a King.
Because Christopher Columbus didn't 'find' America until 1492, and even then, it took years before America became its own country.
#4: A
#5: D
#6: I don't know
#7:E
March 15 44 BC is the answer