What is the difference between a primary source and a secondary source a. a primary source interrupts and analyze secondary sources. b. a primary source was written or created during the time under study. c. a secondary source includes original documents and artifacts. d. a secondary source was written or created during the time under study.

Primary sources provide direct account information, Secondary sources describe, interpret, analyze, summarize and evaluate the views offered by primary sources. Good examples of secondary sources include opinions offered in newspaper articles, movie or book reviews and biographies.

zheng he was a chinese explorer who lead seven great voyages on behalf of the chinese emperor. his seven total voyages were diplomatic, military, and trading ventures, and lasted from 1405 – 1433. however, most historians agree their main purpose was to promote the glory of ming dynasty china.

explanation:

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.