The following examples are primary sources except

a passage from the diary of one of the scientists who discovered lucy
an encyclopedia that provides factual details about the finding of lucy
a photograph of lucy that was taken on november 24, 1974, in ethiopia
an interview with a scientist who was present when lucy was found

An encyclopedia that provides factual details about the finding of lucy

Explanation: A primary source is somebody who was there, or a record made by somebody who was there. Examples of a primary source would be;

  Somebody telling a story about something they were there for

  An account of what happened, written by somebody who was there/part of the process

                   A Secondary source is something that may still be factual, is not coming straight from the mouth of somebody who was there. Examples of a Secondary source;

   A friend telling somebody about what happened to their friend

   And article that was not written by somebody who was there, usually containing quotes from a primary source.

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