Answer:
A usable water can be defined as the water that can be used for the purpose of drinking or can be used for agricultural purposes. The water that can be used is the freshwater.
Saline water is unusable as it has higher level of salts in it, which makes it unsuitable for the drinking purpose and agricultural purpose.
Oceans :unusable
Rivers :usable
Glaciers :usable
Freshwater: usable
Lakes :usable
Groundwater :usable
