How to apply indirect proof or conditional proof in philosophy logic

According to the graph, the manufacturing of products in the united states greatly increased from 1800 to 1900. greatly decreased from the onset of the civil war to 1900. slowly decreased in 1800 and again in 1900. slowly increased after 1880.

Gettysburg address question. what is the purpose of this address?

Why does c. wright mills identify critical thinking as one of the most important criteria for the development of intellectual craftsmanship? why is constantly being aware of the biased nature of your reactions and interactions (what c. wright mills calls self-reflexive) key to the development of that critical thinking? finally, why is keeping a file important, how can it lean to intellectual curiosity which can foster critical thinking and to develop a keen analytical mind?