How many votes are necessary to convict someone who has been impeached?

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:

the government paid religious orders to provide basic education to native american children on reservations. in the late 19th and early 20th centuries, the bureau of indian affairs (bia) founded additional boarding schools based on the assimilation model of the off-reservation carlisle indian industrial school.