Answer:
Through the process of evaporation.
Explanation:
The fisherman could produce distilled water using sea water and plastic bottles. The fisherman takes two bottles and takes seawater in one of the bottle and connect both bottles head to head with each other. Place these bottle in the sunlight, the water in one bottles moves to the other when the water is evaporated due to high temperature gained through solar radiation in this way, salts remained in the second bottle whereas the fist bottle has clean distill water to drink.