Solve using proportionalities by stating the appropriate proportionality law and finding the proportionality constant:

• If a sand pile 4 meters high has a mass of 32000 kg, then what would we expect to be the mass of a geometrically similar sand pile 5.9 meters high?
• If there are 6.24 billion grains of sand exposed on the surface of the first sand pile, how many grains of sand we expect to be exposed on the surface of the second?