How can an older rock layer appear on top of a younger rock layer?

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.

The process by which liquid water changes into water vapour is called what ?

Arow of elements on the periodic table is called an