Identify one river characteristic upstream and in downstream

Why does physical weathering speed up the processes of chemical weathering? a) physical weathering requires abundant water, as does chemical weathering. b) physical weathering produces fresh surfaces for chemical weathering to attack. c) chemical weathering can occur only on small surfaces, not large ones. d) chemical weathering requires salt, which is provided by salt wedging.

The states that the process that have been occurring today have been occurring since earth formed. what is it?

What is the term for a government where power is carefully divided between a central government and several regional or provincial governments? a.) unified or central government b.) federal government c.) confederate government d.) republican government