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1: Ancient Greek Mathematician
3: City in ancient world that had a famous library.
6: If there is not _____ we cannot make measurements.
7: The ___________________ of the Earth is just above 40000 km.
8: The vertical object and the sun ray form an _________________, that need to be calculated in Eratosthenes experiment,

10: The Earth is not flat. It is _______________

2: In Eratosthenes experiment we try to measure the ______________ of a vertical object
6: On 21st of June we have ____________________
10: When day and night are of approximately equal duration all over the planet.
16: Vertical object used in a measurement.