What is the difference between the need for labor unions now and in the 1800s?

in february 1787, congress decided that a convention should be convened to revise the articles of confederation, the nation’s first constitution. in may, 55 delegates came to philadelphia, and the constitutional convention began. debates erupted over representation in congress, over slavery, and over the new executive branch. the debates continued through four hot and muggy months. but eventually the delegates reached compromises, and on september 17, they produced the u.s. constitution, replacing the articles with the governing document that has functioned effectively for more than 200 years.

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation: