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)

Table NS (for one shadow towards the north and  one shadow towards the south)

Table SS (for 2 shadows towards the south)

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