Attrition - rocks smashing into each other and breaking down becoming smaller and smoother
Abrasion - rocks that are in the river wearing down the banks and river bed
Solution - soluble particles dissolving
Hydraulic Action - when there are cracks in the banks / cliffs, water can push air into them which creates pressure causing the cracks to get bigger
Hope this is what you wanted and I hope it helps. :)
They use colors to find regions so you can find them easyer.
Answer:
auto democracy,autocracy,totalitarian,socialism,communism
