A barometer is used to measure air pressure. It is made of a tube of mercury (density of 13 500 kg/m) in an open container. The top of the tube is sealed and contains a vacuum. The bottom is open to the air. During a storm, the mercury is observed to have a height of h = 0.70m. a) What is the air pressure during the storm? b) Mercury is dangerous! Suppose we decided to build a barometer using water h (density of 1000 kg/m) instead of mercury. What would be the height of the water during the storm? The Hindenburg was an airship. It had a very large hydrogen- filled balloon, with a volume of 140 000 m. Below the balloon were heavy engines and room for cargo. The density of air is 1.20 kg/m. The density of hydrogen is 0.09 kg/m. c) What was the buoyant force on the balloon? hydrogen balloon M engines and cargo d) What was the weight force of the hydrogen? e) If the balloon didn't accelerate up or down, what was the total mass of the engines and cargo? Assume that the weight of the balloon fabric is negligible.