Subinfeudation is a term from English law which is a practice of a hierarchical structure of land-owning. The King owns the lands and hires a tenant in which the latter owns another tenant and the tenure continues.
Senators have four year or two year terms. There is another case called 2-4-4 system in which the senators serve one two year, then two four year terms. So that, the answer is correct.
An elected leader in a parliamentary democracy is called a prime minister.
The Federalist Papers are a compilation of 85 essays supporting United States Constitution. Alexander Hamilton, James Madison, and John Jay were the authors behind the essays.