For the given question above, Polyethylene Terephthalate (PET) is a resin of a polyester family making it an organic molecule. Its density is 1.40 g/cm³. The other choices are water (density of 1.00 g/cm³), seawater (1.025 g/cm³), and hot water (less than 1.00 g/cm³). Being that PET is the most dense in relation to the three aforementioned liquids, it would not float atop any. I hope this helps.