6) “If Earth were a ball 25,000 miles in circumference as NASA and modern astronomy claim, spherical trigonometry dictates the surface of all standing water must curve downward an easily measurable 8 inches per mile multiplied by the square of the distance. This means along a 6 mile channel of standing water, the Earth would dip 6 feet on either end from the central peak. Every time such experiments have been conducted, however, standing water has proven to be perfectly level.”

Again, a  pants-on-fire false claim. 

Any experiment done with proper controls (i.e. elimination of refraction as a source of error) shows a curved earth. Not one of these shows no curvature. Ask any certified surveyor or try it yourself. The most-cited experiment is the Bedford Level Experiment (#62). It has been repeated multiple times with proper controls and falsified every single time. 

 https://www.youtube.com/watch?v=RIZbh3g16-8#t=17m43s

The Bedford Level experiment was a series of attempts, beginning in the late 19th century, to show the curvature of the Earth's surface. First conducted by Flat-Earther Samuel Birley Rowbotham, observations along a long straight stretch of drainage canal in the English county of Norfolk seemed to confirm that the Earth is flat. Later measurements by Alfred Russel Wallace, accounting for optic refraction, showed the Earth to be curved. 

Wallace's results were disputed by one of Rowbotham's supporters, one John Hampden. Hundreds of pounds were wagered and disputed. Hampden lost and proved a very bad loser,. Death threats, libel cases, and Hampden's incarceration for breaking injunctions to stop harassing and threatening Wallace and his family ensued.

For more details read : http://blogs.scientificamerican.com/rosetta-stones/wallace-8217-s-woeful-wager-how-a-founder-of-modern-biology-got-suckered-by-flat-earthers/

Anyway, the case is similar to point 3, and many of us, myself included, have seen the curvature of the sea hide first the base and then the tops of cliffs as we sailed out  over the curve. And look at this photograph of the world’s largest sailing ship – see how its hull is hidden below the horizon. The sea is curved.

Source

and this one, by an amateur – more photos and an explanation here

For more on this see the reply to point 138 later.

And here’s another video showing a sailing vessel sinking below the horizon.

https://www.youtube.com/watch?v=7nUFLLUahSI



Here's some more water that isn't level: (click for the large version)