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Google Earth requires a kml file. You can generate a kml file using an Excel file and a free converter like this one.
Export data from CommCareHQ into Excel
If all of the coordinates are in one cell, select the GPS coordinates field and use the Excel "text to columns" feature to separate the GPS field into its 4 component fields (latitude, longitude, elevation, precision). You can delete the elevation and precision columns for a basic map.
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