Kidneys are a filter system. The main job of the kidneys is to remove waste from the blood and return the cleaned blood back to the body. Each minute about one litre of blood ï­ one-fifth of all the blood pumped by the heart - enters the kidneys through the renal arteries.
The volume of helium in the balloon has been estimated as being able to lift a total load, including the balloon material and the structure beneath it, of 65 pounds (29 kg) at sea level and 48 pounds (22 kg) at 8,000 feet (2,400 m).
It would only take four of those to give you the same lift. One balloon that is 30 meters (about 100 feet) in diameter displaces 14,137,000 liters, so it can lift 14,000 kilograms (about 31,000 pounds) -- this is roughly the size of a large blimp. 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: