<span>9000 Pascals
Looking on the internet, it appears that a human can only suck about 3 feet of water. So let's convert that measurement into a few more convenient units.
cmH2O = 36 * 2.54 = 91.44 cmH2O
cmHg = 91.44 * 0.73555912101486 = 67.26 mmHg
Pascal = 91.44 * 98.0665 = 8967 Pascals
PSI = 91.44 * 0.0142233 = 1.3 psi
Since we're dealing with science and the metric system is the most common system used in science, I'd recommend an answer of 9000 Pascals.</span>
It is called observation because you observe with your nose by semlling things your eyes by looking at things your ears by hearing things your tongue by tasting things and your hands by feeling things