The buoyant force must be greater than water.
BMI is a measure of body fat determined by ones Height, Weight, and Gender.
<span>According to Newton's first law of motion:
-- objects at rest will remain at rest unless acted upon by an outside force
-- objects in motion will remain in motion unless acted upon by an outside force
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The transfer of energy means, in convention process, transport of matter. In this case, hot water has lower density than cool water. The water with less density ascends and leaves gaps that are occupied with cooler water "packages".