During the first two years of the american civil war, the war in the east was marked by a) the union siege of richmond. b) the collapse of the confederacy. c) decisive victories for the union. d) significant confederate victories.

its d i found out its d so pick it u weirdos

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.

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