<span><span>Primary sources are original materials on which other research is based, including:<span>original written works – poems, diaries, court records, interviews, surveys, and original research/fieldwork, andresearch published in scholarly/academic journals.
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Secondary sources </span>are those that describe or analyze primary sources, including:<span>reference materials – dictionaries, encyclopedias, textbooks, andbooks and articles that interpret, review, or sythesize original research/fieldwork.
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Tertiary sources are those used to organize and locate secondary and primary sources.<span>Indexes – provide citations that fully identify a work with information such as author, titles of a book, artile, and/or journal, publisher and publication date, volume and issue number and page numbers.Abstracts – summarize the primary or secondary sources,<span>Databases – are online indexes that usually include abstracts for each primary or secondary resource, and may also include a digital copy of the resource.
Hope this helps! :D</span></span></span></span>
Sharp class distinctions divided European society .
D. Western European crusaders conquered the Muslim empires and enslaved most of the people.
The compass, the astrolabe (instrument used to measure latitude), and the rudder <span>all helped European explorers on their quest to find Asia and get rich by by </span><span>buying spices there and selling them in Europe to get a profit.
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