British archeologist John Romer's theory on why the Pyramid Giza was built with such precision involves something simple. What is it?

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Explanation: John Romer was Born in England,he is an Archeological expert,with several Archeological findings in Egypt,he is also a historical icon, he tried tried to know why Pyramid Giza was built with such level of precision,he later found out that it was because of the String that was used for the building. John Romer started his archaeological work in 1966 when he took part at Epigraphic Survey organised by the University of Chicago, the survey took place at the temples and at the tombs in ancient Egyptian site of Thebes.

norsemen from northern countries had made earlier journeys

yes i think there would be volunteers