Most of the world's water is found in two locations. the first is the world's oceans. where is the second location, the one with most of the world's freshwater?

You have been tasked with sorting the rock samples shown into three categories, with two rocks in each category. what attribute would you use to sort these rocks? which rocks would be in each category? rocks: obsidian, coquina limestone, granite, soapstone,pumice, and gneiss.