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.
If you have read the article How Helium Balloons Work, then you know that helium has a lifting force of 1 gram per liter. So if you have a balloon that contains 5 liters of helium, the balloon can lift 5 grams. A normal balloon at an amusement park might be 30 centimeters (about 1 foot) in diameter.To determine how many liters of helium a sphere can hold, the equation is 4/3 x pi x r x r x r.The radius of a 30-centimeter-diameter balloon is 15 centimeters, so: normal balloon at an amusement park might be 30 centimeters (about 1 foot) in diameter. To determine how many liters of helium a sphere can hold, the equation is 4/3 x pi x r x r x r. The radius of a 30-centimeter-diameter balloon is 15 centimeters, so: