The salt vs fresh is the clear part of the question. The indeterminate part is just how buoyant the object is. Without knowing that, there's no way to tell whether the change to fresh water means it floats a bit less, or is neutral, or sinks. All you know for sure is it is a little less floaty in fresh water. But there is insufficient information to tell you how much less floaty.I will not give away the answer, but it has to do with the density of the fluid. The fluid with the greater density will create more buoyancy upon the object.
SeaRat