Answer:
Sand
Explanation:
While the term buoyancy may confuse the reader, the question here is referring to buoyant force.
Buoyant force is the amount of pressure exerted on an object by the liquid it is in. Given by the formula
[tex]F_{b} = V_{o} D_{l} g[/tex]
Where
[tex]F_{b}[/tex] = Buoyant Force
[tex]V_{o}[/tex] = Volume of Object submerged in the liquid
[tex]D_{l}[/tex] = Density of Liquid
[tex]g[/tex] = Force of gravity
Since in this question the swimmer with the sand is completely submerged in water, more of the volume of his preserver is under the water hence the buoyant force is greater on it than the swimmer with the Styrofoam (as part of him is not submerged in water)
