The pathogenesis of ectopic gastric mucosa is a matter of debate between a congenital-embryological-and an acquired origin-consecutive to a gastroesophageal reflux (GER) like Barrett's esophagus -, the most commonly accepted theory being that these areas are embryological remnants.
Standard size latex filled helium balloons stay afloat for approx 8 - 12 hours, metallic helium filled balloons float for 2-5 days. I have found that a 36 latex helium filled balloon can stay afloat for a number of days due to the thickness of the balloon and the massive quantity of helium.
Calculating Altitude. In order to calculate how high a balloon could go before popping, you need to calculate the density of a helium balloon that has a radius of 0.1143 mm. Calculate the volume of the balloon using the formula for the volume of a sphere; then use the volume to calculate the density.n 1987, a British man, Ian Ashpole, set the reported world record for highest helium-balloon flight. Using 400 helium balloons with radii of one foot, he achieved the height of one mile, 1,575 yards without any of the balloons popping. This figure is the highest recorded altitude of a helium balloon.