Please help im stuck i dont get it

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.

Afathom is a unit of length, usually reserved for measuring the depth of water. a fathom is approximately 6 ft in length. take the distance from earth to the moon to be 230,000 miles, and use the given approximation to find the distance in fathoms.

Compare nato and the eu; list 2 similarities contrast nato and the eu; list 2 differences what did you learn about nato and the eu? were you surprised by any of it? 1st answer will get brainliest