It's easy to disprove this flat earth bullshit. Go climb a mountain, take a long straight ruler or some other object that is long and straight. Watch for jetliner contrails that you can see from one horizon to the other with few/no hills in the way. Hold the straight edge up and line it up as closely as you can to each point in the horizon. If the earth is flat the contrail will also be flat, and your straight edge will align with the contrail. Guess what you will see?
Yes, I've done this as a way to prove to my two girls that the earth is round, just like the pics from space show us. Good God! In the 21st century we still have retards!