2. Dentists have recommended that a toothbrush be kept at least 6 feet away from a toilet to avoid airborne particles resulting from the flush.
4. No piece of paper can be folded in half more than 7 times.
5. Duck's quacks do not echo
2. This was busted in mythbusters in their 12th episode: Episode 12: "Break Step Bridge, Toothbrush Surprise, Rowing Water Skier". They tested toothbrushes left in the bathroom and even had control versions located in the kitchen (more than six feet away) and they found that "fecal coliforms bacteria can grow in toothbrush bristles, including the control ones. However, none were of a level high enough to be dangerous, and experts confirm that such coliforms were impossible to completely avoid."
4.Not true. Busted in Mythbusters when they were able to fold a paper 11 times. The myth is originally that you cannot fold a paper no matter its size more than 7 times. It was impossible to fold a piece of letter-sized (8.5" x 11", 216 mm x 279 mm) 20 lb (37 g/m2) copy paper with perpendicular folds more than seven times. The thickness of the paper exponentially grew with each successive fold, and after the seventh fold the paper was just too thick to fold without breaking. The MythBusters then laid out a football field-sized sheet of interconnected paper (170 ft x 220 ft, 51.8 m x 67.1 m), and due to the reduction of its thickness-to-area ratio, were able to perpendicularly fold the paper 11 times.
5.Another myth busted by Mythbusters.When examined by an audio-expert, it was found that the echo was "swallowed" by the original quack, due to the very similar acoustic structure between the quack and the echo. Because of this, it may be difficult to tell where the quack ends and the echo begins.
sorry...