how much of the earths water is stored in lakes, rivers,ground, atmosphere, Marsh and vegetation?

How much of the earths water is stored in oceans, ice caps and glaciers?

what is overland flow?

What is through flow?

Groundwater flow

What are the three Hydrological processes?

What are the causes of river pollution?

How do you manage river pollution?

What are the three types of small scale water schemes?