What is a historians job when looking at primary sources

What is one result of the supreme courts decision in the mccullough v maryland case

Me! these questions are based on american people in the south essential questions: question 1: for what reasons will one group of people exploit another?focus questions: question 1: what influenced the development of the south more: geography, economy, or slavery?question 2: what were the economic, political and social arguments for and againsts slavery in the first half of the 19th century.

This is the name of the 17th century conflict between those loyal to parliament and those loyal to british monarchy