D - to explain the structure and role of state governments.
Article 2 of the Confederation is all about State Sovereignty stating that the states have the power to keep its freedom, independence and power.
12,000+ ago (it may or may not be right)
To interpret laws is what the Judicial Branch does as its main purpose.
Qualitative data is a categorical measurement expressed not in terms of numbers, but rather by means of a natural language description