Buoyancy and Density, Good or Bad?

An object will sink or float by its density and buoyancy.  If an object can float then the buoyancy of that object is positive.  If the object sinks then buoyancy is negative, and if the object neither sinks or floats then it's neutral.  If you were on a ship you would need to know the buoyancy of the water so you dont sink or go to slow.  If you compare a lake and rock the molecules in the rock are closer together than in the lake so the rock would sink.  To find an objects density you divide the objects mass by the volume.  Density is the physical property of matter and is in everything.  If I was in the pool I would just be standing there with some of my body in the water, but if I was less dense I would float and not ever be able to swim ( bad I know).  When you push a liquid away thats called displacement.  The dead sea has a lot of salt and because of the salt we can float without trying and we can also eat it.