An object has a density that is greater than the density of water. how could you make it float? explain by giving a real-life example.

An example is a submarine.
As a submarine dives, the ballast tanks are flooded with water and the air in the ballast tanks is vented from the submarine until its overall density is greater than the surrounding water and the submarine begins to sink (negative buoyancy).

Answerigneous bedrock of the oceanic crust;

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