One reason is for safety! in case you get stranded in a body of water you can keep yourself afloat
Gas and plasma .............
Answer:
When conducting research, scientists use the scientific method to collect measurable, empirical evidence in an experiment related to a hypothesis (often in the form of an if/then statement), the results aiming to support or contradict a theory.
Explanation:
I don't know if it can help you
Density is mass of object per unit volume
