layer puzzle

I think that the order is  4,5,2, b, a ,6,1 & 3 because 4 is lowest then 5 then. Then 2 because the intrutions are younger than everything they cut through. Next is B because it cuts through 5 and 4 then A because it levels it out. Next is 6 and 1, after that is 3 because it cuts through all of them.

All the rocks have Layers. There are many layers and that is probably one of the reasons that they think the world is so old. Layers build up over time and the layers of rock show that is has been a long time.