Helium Balloons to Lift a Human

How many helium balloons can it take to lift a human, what is Britain's stainiest food, Brainiac for a day blows up some melons, another Hollywood star pays us a visit, what is the best way to get rid of stress, can you eat upside-down, can you locate water by dowsing, Oliver Skeete faces the electric chair and we send more caravans into orbit.