1/3
7 Months of Service
That would require then to use their brainsWhy.. not just buy a plane ticket? You can quite easily see the curve from a plane window, and it's FAR cheaper than literal rocket science.
And even if they believe that all commercial planes have fisheye windows or something stupid, then it's still easier and cheaper to get your own pilot's license, built an entire kit plane from scratch so you know exactly how it's built, then fly that and see the curve..
=,=
Brains are round...ish
Flat earthers don't like round things
you do the math
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