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).
An educational, Fair Use website. A balloon is a bag filled with heated air or a light gas so that it rises and floats in the air. A balloon rises because the heated air or gas inside is less dense than the surrounding air. There are two chief kinds of balloons: hot-air balloons and gas balloons. Hot-air balloons are mainly use for sporting and they rise because the air inside the balloon is warmer and lighter than the surrounding air.