Download Geogebra Classique 5: https://www.geogebra.org/download
Draw easily the figure, just by copy/paste of 2 lines data from the Eratos Google spreadsheet
Download and open one of the 3 model files: Download Zip File
Table NN (for 2 shadows towards the north) |
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Table NS (for one shadow towards the north and one shadow towards the south) |
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Table SS (for 2 shadows towards the south) |
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. Link to the shared google spreadsheet to register your measurement: